Digital information carrier

ABSTRACT

[Problem to be Solved] To provide a digital information carrier which enables blending of cluster information carrier comprising of image objects joined together to other viewable content (a character, an image, background, etc.) of a document, to seamlessly unify a printed document and an electronic document when accessing the cluster information carrier by an image recognition means, such as partial scanning, and to perform a method for finding positional information and processing commutative with the written contents of the document without incorrect recognition at high speed and a method for recognition. 
     [Solution Means] A digital information carrier comprising of a plurality of image objects as constituent elements, containing a cluster information carrier constituted by at least two image objects, and having bit data correlated to the relative relationship of at least two image objects concerned serving as configuration elements were used. In addition judgment conditions of whether the two image objects concerned serving as configuration elements constitute a cluster information carrier were correlated to the above-mentioned cluster information carrier. Furthermore, configuration of a logical block obtained by unifying a plurality of unit information carriers which are the minimum units at the time of decoding bit data from a digital information carrier was realized, and configuration of a new logical block was enabled by replacing at least one of the configuration elements of the concerned logical block with the above-mentioned unit information carrier adjacent to the logical block concerned.

TECHNICAL FIELD

Present invention relates to increasing the amount of information byapplying digital information carrier to the document displayed.

Specifically, it relates to blending a cluster information carriercomprising of image objects joined together to other viewable contents(a character, an image, background, etc.) of a document, to accessingthe digital information carrier by an image recognition means, such aspartial scanning, to unifying a printed document and an electronicdocument seamlessly, and to providing a method for finding positionalinformation on the document and for performing processing commutativewith the written contents of the document.

BACKGROUND ART

The technology for making the information coded as bit data and anelectronic document correlate and unify within a printed document isknown well.

The concept of 1-dimensional or 2-dimensional barcodes and the usage foracquiring the positional information on a document based on theinformation added to the printed document is disclosed (refer to PatentReferences 1-8, for example).

An invention which unifies barcodes of different dimensions is alsodisclosed (for example, Patent Reference 9). As a specific example, adigital information carrier wherein 1-dimensional and 2-dimensionallayers are unified is shown there.

A barcode of 1-dimensional and 2-dimensional layers having a multilayerstructure is also disclosed (for example, Patent References 10 and 11).

It is also disclosed how to integrate a barcode in an image or a secretdocument (for example, Patent References 12-19).

A data coding method performed using an illustration symbol is alsodisclosed (for example, Patent References 20 and 21).

A method for coding by using at least two sorts of symbols and arrangingthese symbols in a matrix shape on various media wherein a documentdisplay is possible (for example, Patent Reference 22) is alsodisclosed. As a specific example it is shown how to use a monochromelattice-like pattern.

The method of combining a plurality of 2-dimensional dot codes usingdifferent colors is also disclosed (for example, Patent References23-26).

Dot Code

A technology based on a self-synchronous type of symbols called “glyphs”is also disclosed (for example, Non-Patent Literature 1). It isindicated that glyph positions provide for the glyph clocking mechanism,and that glyph orientations provide for information to be digitallyencoded.

In addition, a method for showing positional information using glyphsover the whole predetermined region of a document is also disclosed (forexample, Patent Reference 27). It is indicated that each glyph is shownby a line segment inclined to the left or to the right that provides for1 bit of information. Furthermore, other glyphs which can code 2 bits ofdata are disclosed (for example, Patent Reference 28). It is indicatedthat such glyphs are expressed in a triangular shape and have fourdifferent directions, this providing for 2 bits of information perglyph.

[Patent Reference 1] U.S. patent application publication Ser. No.20020027165

[Patent Reference 2] U.S. Pat. No. 6,418,244 B2

[Patent Reference 3] U.S. Pat. No. 6,176,427 B1

[Patent Reference 4] U.S. Pat. No. 5,617,358

[Patent Reference 5] U.S. Pat. No. 6,070,805

[Patent Reference 6] U.S. Pat. No. 5,742,041

[Patent Reference 7] U.S. Pat. No. 6,043,899

[Patent Reference 8] JP Patent Application Publication Heisei 7-306904

[Patent Reference 9] U.S. Pat. No. 006,398,117

[Patent Reference 10] JP Translation of PCT International Application WO96/18972

[Patent Reference 11] U.S. Pat. No. 5,525,798

[Patent Reference 12] U.S. Pat. No. 5,525,798

[Patent Reference 13] U.S. Pat. No. 6,256,398 B1

[Patent Reference 14] U.S. Pat. No. 05,522,623 A

[Patent Reference 15] U.S. patent application publication Ser. No.20020060396

[Patent Reference 16] EP Patent No. 1154373 A2

[Patent Reference 17] JP Patent Application Publication 2001-320573

[Patent Reference 18] JP Patent Application Publication 2002-36763

[Patent Reference 19] JP Patent Application Publication 2002-63142

[Patent Reference 20] FR Patent No. 2809210 A1

[Patent Reference 21] U.S. Pat. No. 6,460,766 B1

[Patent Reference 22] U.S. Pat. No. 6,273,340 B1

[Patent Reference 23] EP Patent No. 1178428 A1

[Patent Reference 24] JP Patent Application Publication 2000-293644

[Patent Reference 25] JP Patent Application Publication 2000-293645

[Patent Reference 26] JP Patent Application Publication 2000-293646

[Patent Reference 27] U.S. Pat. No. 6,327,395 B1

[Patent Reference 28] U.S. Pat. No. 5,245,165

[Non-Patent Literature 1] Hecht D., Printed Embedded Data Graphical UserInterfaces, Computer, March 2001, pp. 47-55

DISCLOSURE OF INVENTION Problems to be Solved by the Invention

In any of the prior art, however, the problem of recognition errors isnot completely overcome. Reasons for recognition errors can beclassified into several cases which will be explain here.

Ghost Dots

It means appearance of noise and stains, such as blots that occur at thetime of printing. When a digital information carrier is constituted bydots, this has significant impact and it is commonly addressed bydefining a lattice for arranging and removing image objects.

Recognition Errors Due to Display Distortion

This occurs when an image object is displayed or recognized whiledeviating from the ideal form at the time of displaying or reading adigital information carrier. Specifically, at the time of displaying thecause is variation in the sending and printing speed, and at the time ofreading the cause is variation in the scanning speed of a scanner, tiltof a camera, etc. This influence becomes significant, especially withmultiple image objects, such as two dimensional codes. In addition todisplay distortion, when coding bit data in the color of an imageobject, the gap from the ideal color, that is, the color difference,similarly leads to recognition errors.

Recognition Errors Due to Incorrect Recognition of the Coordinate System

Incorrect information will be generated, for example, if a digitalinformation carrier is read while the document is upside down and it isdecoded without taking that into account. This becomes especiallyproblematic when highly symmetrical image objects are used.

Other Recognition Errors

When there is an image object that is partially difficult to recognizein the recognition range, the whole image object in the recognitionrange may become impossible to decode, or may be incorrectly recognized.This becomes especially problematic when acquiring one piece ofinformation from a group consisting of a plurality of image objects in apredetermined range.

When attempting to increase the amount of retained information of adigital information carrier, the display density of the image becomeshigh, and the possibility of the above-mentioned incorrect recognitionincreases. In addition, it is also problematic when measures performedin order to avoid incorrect recognition reduce the display flexibilityof a digital information carrier, or complicate the processing foracquiring information and reduce the processing speed.

Therefore, a digital information carrier which can easily display largevolume of information, has low possibility of incorrect recognition, andis easy to process at high speed is called for.

The objective of this invention is to provide a digital informationcarrier which solves these problems and to provide a method and a systemfor handling it.

Means for Solving the Problems

The digital information carrier, concerning the 1st aspect of thisinvention, offered in order to solve the above-mentioned problemscomprises of a plurality of image objects as constituent elements,contains a cluster information carrier constituted by at least two imageobjects where the cluster information carrier is characterized by havingbit data correlated to the relative relationship of at least two imageobjects used as constituent elements.

Here, a digital information carrier is an aggregate of image objectsobtained by coding bit data where an image object consists of aggregatesof image pixels.

In addition, relative relationship means the relationship of the formsof a plurality of image objects, such as difference of forms or colors,the longest principal diameter ratio, etc., and the relationship of thepositioning of a plurality of image objects, such as distance betweenthe centers of gravity, a relative angle, etc.

Since it is possible to specify many relationships as a relativerelationship as mentioned above, it is possible to have more bits ofdata correlated to one cluster information carrier than to have bits ofdata correlated to each constituent image object. That is, it ispossible to display a lot of information by one cluster informationcarrier. For this reason, the amount of configuration image objects in adigital information carrier decreases, and lowering the display densityof an image is realized. Therefore, the influence of a ghost dots etc.decreases since it becomes hard be recognized incorrectly, and a digitalinformation carrier that is displayed and processed with a fastrecognition speed is realized.

In addition, since large volume of information can be displayed with onecluster information carrier a lot of information can be displayed insmall image display domains. Therefore high resolution and precision canbe achieved when the digital information carrier displays positionalinformation.

Further, general image processing can be done by form extraction methodsbased on existing technologies concerning image recognition of a clusterstructures. This ensures higher image-processing speed and minimizes thepossibility for incorrect recognition. Therefore, a high-density displaycan be attained and the digital information carrier that supports largervolumes can be realized.

The digital information carrier concerning the 2nd aspect of thisinvention, offered in order to solve the above-mentioned problems is thedigital information carrier concerning the 1st aspect of this invention,including relative relationship to which bit data does not correlate andcan be arbitrary constituted among the relative relationships of theimage objects constituting the cluster information carrier.

The digital information carrier concerned creates a cluster informationcarrier which displays the same bit data while having different forms bymaking arbitrary the relative relationships to which bit data does notcorrelate. For this reason, high flexibility can be obtained in adisplay form. Therefore, display distortion can be avoided andembodiments based on selection of forms which are easy to display, orforms which are easy to distinguish from a ghost dot and are easy to berecognized can be realized. Furthermore, when a digital informationcarrier is integrated in an existing document display, an embodimentbased on a form that does not stand out can be selected.

Digital information carrier concerning the 3rd aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 1st or 2nd aspect of this invention,and at least one of the image objects serving as a constituent elementof one cluster information carrier that serves as a constituent elementof other cluster information carriers.

In the digital information carrier concerned, different clusterinformation carriers share some of the image objects. For this reason,cluster information carrier is displayed with high density. Therefore,digital information carrier supporting larger volumes is realized.

Digital information carrier concerning the 4th aspect of this inventionoffered in order to solve the above-mentioned problems comprises aplurality of image objects as constituent elements and contains acluster information carrier constituted by at least two image objects,and the cluster information carrier is characterized by having thejudgment conditions of whether these at least two image objectsconstitute a cluster information carrier correlated to the relativerelationship of the at least two image objects used as constituentelements, and by having bit data correlate using the cluster informationas the unit.

Here, the whole processing for carrying out judgment is called a clusterfunction.

In the digital information carrier concerned, before decoding generatesbit data, it is specified about each image object which constitutesdigital information carrier whether it is the object of decoding. Forthis reason, it is easy to identify a ghost dot and incorrectrecognition is not likely to occur. In addition, different judgmentconditions can be set in the judgment of the same cluster informationcarrier. For this reason, it is realized to set a different clusterfunction for every display mode. Specifically, it is realized to set acluster function suitable for a print or a cluster function suitable forelectronic display. Occurrence of incorrect recognition is furthersuppressed by setting the optimal cluster function for every displaymode like this.

Digital information carrier concerning the 5th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 4th aspect of this invention, and thecluster information carrier to be judged has bit data correlated to therelative relationship of a plurality of image objects which areconstituent elements.

It is realized to have many bit data correlated to one clusterinformation carrier in the digital information carrier concerned. Forthis reason, the amount of constituent image objects of a digitalinformation carrier decreases, and it is realized to lower the displaydensity of an image. Therefore, the influence of a ghost dot etc.decreases and a digital information carrier which is not likely to berecognized incorrectly, is easy to display and with a fast recognitionspeed is realized.

Furthermore, since it is confirmed in the stage of judging it being acluster information carrier that the relative relationship is apredetermined relationship, a digital information carrier with whichincorrect recognition is especially not likely to occur is realized.

Digital information carrier concerning the 6th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning one of the 1st-5th inventions of thisapplication, and predetermined information is given to the relativearrangement of the cluster information carriers.

A possibility that a ghost dot has a specific relative arrangement withother image objects is low as mentioned above. For this reason, wheninformation is contained in the relative arrangement of the clusterinformation carriers like the digital information carrier concerned, itis identified easily that it is a ghost dot in the process of generatingthat information. Therefore, a digital information carrier with whichincorrect recognition does not easily take place is offered.

In addition, since the information will be double-checked when the bitdata held by the cluster information carriers are also given to therelative arrangement, a digital information carrier with which incorrectrecognition especially does not easily take place is offered.

Furthermore, since the amount of information per unit display area willincrease when different information from the bit data held by clusterinformation carriers is given, a high-density display is attained and adigital information carrier supporting that of larger volume is offered.

In addition, since it also becomes possible to unify the bit data heldby a plurality of cluster information carriers and create oneinformation when coding one information by combining cluster informationcarriers and the relative arrangement, a digital information carriersupporting that of larger volume is offered. Moreover, since oneinformation is created by combining a plurality of decoding processes,it becomes a digital information carrier wherein informational secrecyis improved.

Digital information carrier concerning the 7th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 6th aspect of this invention, and theinformation given to the relative arrangement is the informationconcerning the unifying rule for unifying the bit data correlating to aplurality of cluster information carriers and generating oneinformation.

In the cluster information carrier concerned, since the clusterinformation carrier has the bit data used as the basis of oneinformation and the relative arrangement has the information about theunifying rule, there is a very large amount of information which thedigital information carrier can display. Therefore, a digitalinformation carrier supporting that of larger volume is realized. Inaddition, the thing which is a group of the minimum units in decoding ofthe cluster information carrier, etc. and can build one informationunder a predetermined unifying rule is called a logical block.

Digital information carrier concerning the 8th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 6th or 7th aspect of this invention,and the information concerning either the coordinate axis or thedirection of the cluster information carrier arrangement is given to therelative arrangement of the cluster information carriers.

With the cluster information carrier concerned, attribution of thecoordinate axis or the direction is realized only by recognizing therelative arrangement. For this reason, it is not necessary to make theadditional information about the coordinate axis or the directioncorrelated to the cluster information carriers, and the amount ofinformation which the cluster information carriers can code increasesrelatively. Therefore, a digital information carrier supporting that oflarger volume is realized.

In addition, even if symmetry of the cluster information carrier itselfis high, recognition of the coordinate axis or the direction is easilyattained. Generally, the cluster information carrier having highersymmetry has higher display ease, and is not likely to be recognizedincorrectly as cluster information carrier. For this reason, if the onehaving high symmetry of the cluster information carrier itself and theinformation on the coordinate axis or the direction is given to therelative arrangement, a digital information carrier which is not likelyto be recognized incorrectly will be realized.

Digital information carrier concerning the 9th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 8th aspect of this invention, and thearrangement interval of the above-mentioned cluster information carriersarranged 2-dimensionally is set for every coordinate axis.

If the coordinate axis is incorrectly recognized, it will become verydifficult to acquire the right information. For this reason, recognitionof the coordinate axis is especially important in order to avoidincorrect recognition. In the cluster information carrier concerned,since the coordinate axis is attributed easily only by recognizing thearrangement interval, a digital information carrier which is especiallynot likely to be recognized incorrectly is realized.

Digital information carrier concerning the 10th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 8th or 9th aspect of this invention,and among d number of cluster information carriers (wherein d≧4) whichare arranged consecutively, e number of cluster information carrierswhich fulfill the conditions of e<d/2 are arranged out of alignment inthe direction which intersects perpendicularly to the arrangementdirection formed of the remaining d-e number of cluster informationcarriers, and the information concerning the coordinate axis is given tothe arrangement direction and the information concerning the directionis given to the gap of misalignment.

When the digital information carrier concerned has a 1-dimensionalarrangement, it is realized to judge whether it is the arrangement ofthe forward direction or the arrangement of the backward direction bysetting always constant the gap direction to the arrangement directionformed of the remaining d-e number of cluster information carriers.

In addition, when the digital information carrier concerned has a2-dimensional arrangement, by making the arrangement direction formed ofthe remaining d-e number of cluster information carriers to agree withone coordinate axis and by enabling judgment of which the positivedirection of this coordinate axis is by the gap direction, it isrealized to also recognize about the other coordinate axisunambiguously.

Thus, by setting the gap direction appropriately, before decoding eachcluster information carrier, the coordinate axis and the direction areattributed easily from the arrangement interval. For this reason, adigital information carrier which is not likely to be recognizedincorrectly is realized.

Digital information carrier concerning the 11th aspect of this inventionoffered in order to solve the above-mentioned problems is characterizedin that configuration of a logical block formed by unifying a pluralityof unit information carriers which are the minimum unit at the time ofdecoding bit data from a digital information carrier is enabled, thatone information is given to the arrangement formed by unifying someconstituent elements in the logical block, and that configuration of anew logical block is enabled by replacing at least one constituentelement of the logical block with a unit information carrier adjacent tothe logical block.

Here, a unit information carrier is a cluster information carrier or animage object. In addition, a logical block is a group of unitinformation carriers, it is possible to build one information under apredetermined unifying rule, and, generally it refers to the thingwherein unit information carriers are arranged in the shape of a matrix.In addition, a group of the bit data formed by decoding each unitinformation carrier constituting a logical block may also be called alogical block.

Since the replacement of unit information carrier which constitutes thelogical block concerning this invention is permitted, the form of alogical block may change at any time. Since it differs from aconventional logical block at this point, it is also called a virtualblock. Therefore, in the subsequent explanation, a logical block may beused in a meaning including a conventional logical block and aconventional virtual block.

Since the form of a virtual block can change as mentioned above, whenthe recognition range which is the scope of recognition of digitalinformation carrier moves according to the movement of an input device,it is also realized to form a new virtual block suitably by repeatingreplacement and to follow the movement of the recognition range.Therefore, the situation where recognition becomes impossibletemporarily with the movement of the recognition range is not likely tooccur, and a digital information carrier which is not likely to berecognized incorrectly is realized.

In addition, even if a part of the image object in the recognition rangebecomes impossible to recognize, it is also realized to avoid this andto form a virtual block. For this reason, predetermined information isrealized even when it is not necessarily good in the stage ofrecognizing an image. Therefore, a digital information carrier which canconstitute the virtual block concerned is impervious to disturbance, andis not likely to be recognized incorrectly.

Digital information carrier concerning the 12th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 11th aspect of this invention, and alogical block (virtual block) is constituted from more unit informationcarriers than the number of elements of the arrangement to which oneinformation is given.

In the digital information carrier concerned, it is realized to use unitinformation carrier which is not involved in the configuration of oneinformation as redundant carrier. For this reason, even if it becomesimpossible recognizing a part of unit information carrier in a virtualblock, it may be able to complement with redundant carrier. In addition,the number of the redundant carriers in a virtual block may be setaccording to a display mode. Specifically, since the possibility ofincorrect recognition is high with a digital information carrier createdwith a common printer of low dpi etc., the number of redundant carriersis set to many, and since the possibility of incorrect recognition islow with a digital information carrier created with a high-qualityprinting machine etc., the number of redundant carriers is set to a few.In addition, although it is easy to avoid incorrect recognition when thenumber of redundant carriers increases, since the number of constituentelements of a virtual block increases, the processing load for acquiringone information increases.

Digital information carrier concerning the 13th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 11th or 12th aspect of thisinvention, and unit information is the information which can identifythe arrangement coordinates of any constituent element of the logicalblocks (virtual block).

In the digital information carrier concerned, it is realized to acquirethe positional information by recognizing a virtual block, and further,even if the recognition range moves minutely, it is realized tocontinuously offer suitable positional information.

Digital information carrier concerning the 14th aspect of this inventionoffered in order to solve the above-mentioned problems contains bitmatrix V formed by arranging the arrangement element bm (m=0-n−1) of thebit arrangement B for reference having the arrangement length nspecified beforehand in the shape of a matrix, bit data is made tocorrelate this bit matrix, two matrix elements v (i, j) and v (i+1, j)adjacent to one (i-axis) of the two arrangement axes of the bit matrix Vfulfillv(i,j)=bmv(i+1,j)=bm+1

and when the amount of gaps on the side of the j-axis of the arrangementelement bm is a, two matrix elements v (i, j) and v (i, j+1) adjacent tothe other arrangement axis (j-axis) of the bit matrix V fulfillv(i,j)=bmv(i,j+1)=bm+a

and the amount of gaps a on the side of the j-axis is characterized bybeing an integer of 2 or more.

Regardless of which arrangement element is used as the starting point ofthe bit matrix V concerned which is obtained by decoding digitalinformation carrier, the bit arrangement obtained by unifying theconstituent elements of the logical block wherein the number ofarrangement of the main scanning direction is a configures a partialarrangement of the reference bit arrangement. For this reason, it isrealized to form a logical block using an arbitrary place as thestarting point, and it enables to avoid the matrix element which was notrecognized well and to build a logical block. Therefore, it is avoidedthat recognition incapability of a part makes recognition of the wholerecognition range difficult, the recognition speed improves as a result,and the possibility of incorrect recognition also falls.

Digital information carrier concerning the 15th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 14th aspect of this invention, and itis made possible to form the same partial arrangement as that of the bitarrangement B for reference by setting the positive direction of thei-axis as the main scanning direction and the positive direction of thej-axis as the sub-scanning direction about the logical block which is apartial matrix of the bit matrix V wherein any one matrix element v (i,j) is used as the starting point and the arrangement length on the sideof the i-axis is set to the amount of gaps a, and by unifying some ofthe constituent elements of the logical block (virtual block).

Digital information carrier which can constitute the virtual block whichforms the same bit arrangement as the partial arrangement of the bitarrangement B for reference in such unifying uses an arbitrary place asthe starting point, and constituting a virtual block is realized. Forthis reason, since the judgment of whether it constitutes a blockcompared with the conventional logical block is performed quickly, therecognition speed is high, and a digital information carrier with whichincorrect recognition does not easily take place is realized.

In addition, the virtual block formed by setting the arrangement lengthon the side of the i-axis to a can form a matrix. Since it is matrixform, recognition becomes easy. Therefore, a digital information carrierwith which incorrect recognition does not easily take place is realized.

The digital information carrier concerning the 16th aspect of thisinvention offered in order to solve the above-mentioned problems is thedigital information carrier concerning the 15th aspect of thisinvention, and the bit arrangement B for reference is constituted sothat the partial arrangement of the predetermined length obtained byarbitrary offset differs from others mutually.

This way, the logical block built can acquire one offset value bycomparing with the bit arrangement B for reference the arrangementobtained by unifying constituent elements. If this offset value is usedas the positional information which specifies which portion of thedigital information carrier the logical block is, it is easily realizedto acquire the positional information by recognizing the imageconcerning the logical block in the recognition range.

Digital information carrier concerning the 17th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning the 15th or 16th aspect of thisinvention, and configuration of a new logical block (virtual block) isenabled by replacing the matrix element v (i, j) which serves as the endof the main scanning direction arrangement which constitutes a logicalblock (virtual block) on the condition that either of the matrixelements v (i-a, j+1) and v (i+a, j−1) is adjacent to the logical block(virtual block).

The virtual block newly built this way may change its form withreplacement. For this reason, forming a virtual block is realized whileavoiding those of which recognition is difficult among the image objectsrecognized. Therefore, a digital information carrier equipped with theconcerning configuration does not easily produce incorrect recognition.

Digital information carrier concerning the 18th aspect of this inventionoffered in order to solve the above-mentioned problems is the digitalinformation carrier concerning one of the 15th-17th inventions of thisapplication, and configuration of a new logical block (virtual block) isenabled by removing the matrix element which constitutes the first ofthe bit arrangement from a logical block (virtual block), and bycomplementing the matrix element adjacent to the matrix element whichconstitutes the last of this bit arrangement on the side of the mainscanning direction.

In addition, digital information carrier concerning the 19th aspect ofthis invention offered in order to solve the above-mentioned problems isthe digital information carrier concerning one of the 15th-17thinventions of this application, and configuration of a new logical block(virtual block) is enabled by removing the matrix element whichconstitutes the last of the bit arrangement from a logical block(virtual block), and by complementing the matrix element adjacent to thematrix element which constitutes the first of this bit arrangement onthe opposite side of the main scanning direction.

Any virtual block built this way may change its form. For this reason,forming a virtual block is realized while avoiding those of whichrecognition is difficult among the image objects recognized. Therefore,a digital information carrier equipped with the concerning configurationdos not easily produce incorrect recognition.

Display medium concerning the 20th aspect of this invention offered inorder to solve the above-mentioned problems is the one for displayingthe digital information carrier concerning for one of the 1st-19thinventions of this application. As long as the medium can display in themode which can detect a digital information carrier, it may not only bepaper or a film but may be any sort of medium.

In addition, display device concerning the 21st aspect of this inventionis the one for displaying the digital information carrier concerning forone of the 1st-19th inventions of this application. The device refers toone for displaying a digital information carrier by display elements,such as liquid-crystal-display element, CRT, EL display element, digitalpaper, etc.

In addition, recording medium concerning the 22nd aspect of thisinvention is the one for recording the digital information carrierconcerning for one of the 1st-19th inventions of this application. Thedisplay data is data for displaying a predetermined digital informationcarrier on a display medium or a display device which is made possibleto be stored in a recording medium. In addition, this recording mediumrefers to magnetic recording media, such as FD, a hard disk, magnetictape, etc., optical recording media, such as CD and DVD, magneto-opticalrecording media, such as MO, etc.

System for creating digital information carrier concerning the 23rdaspect of this invention offered in order to solve the above-mentionedproblems is equipped with an input device for data input, a processingdevice for processing the inputted data and for generating dataconcerning digital information carrier consisting of a plurality ofimage objects, and an output device for outputting data concerning thegenerated digital information carrier, and the processing device ischaracterized by comprising conversion means for converting the inputteddata into bit data and a generation means for identifying at least twoimage objects correlating to the bit data converted by the conversionmeans and the relative relationship of these and for generating imagedata of cluster information carrier which consists of at least two imageobjects based on the specified contents.

It is realized by the system concerned to output from the output devicea digital information carrier which contains cluster information carrierand can avoid incorrect recognition.

System for creating digital information carrier concerning the 24thaspect of this invention offered in order to solve the above-mentionedproblems is the system for creating digital information carrierconcerning the 23rd aspect of this invention, and when the amount ofdata of the bit data obtained by the conversion means is more than themaximum amount of data which one cluster information carrier candisplay, the bit data after conversion is transformed into a bitarrangement which uses bit data having the data size below the maximumamount of data as an element by the conversion means, and by thegeneration means, while image data of a plurality of cluster informationcarriers are generated to correlate to the bit data which serve as eachelement of the bit arrangement, the display position of a plurality ofthe image data is determined to correlate to the arrangementrelationship of the bit arrangement.

According to the system concerned, a plurality of cluster informationcarriers are outputted from the output device so that a bit arrangementcan be formed from the relative position of those. For this reason, itis realized to generate data having a data size bigger than the maximumamount of data which one cluster information carrier can display asdecoded information by recognizing the relative arrangement of aplurality of cluster information carriers.

System for creating digital information carrier concerning the 25thaspect of this invention offered in order to solve the above-mentionedproblems is the system for creating digital information carrierconcerning the 23rd or 24th aspect of this invention, and the processingdevice equipped with an input/output part which exchanges a data signalswith the input device and the output device, a processing part whichprocesses the data inputted from the input/output part, and a memorypart which records the data required in order for the processing part tocarry out data processing, the memory part has image data of the clusterinformation carrier and data concerning the correspondence relationshipbetween the cluster information carrier and the bit data, and thegeneration means comprise means for selecting cluster informationcarriers correlating to the bit data converted by the conversion meansbased on the correspondence relationship data stored in the memory part,reading means for reading the image data correlating to the selectedcluster information carriers from the memory part, and determinationmeans for determining the display position of the image data of the readcluster information carriers.

According to the processing device concerned, it is realized to form acluster information carrier which displays the inputted data by havingthe processing part suitably exchanging data with the memory part.

Method for creating a digital information carrier concerning the 26thaspect of this invention offered in order to solve the above-mentionedproblems is a method for creating a digital information carrier carriedout by the processing device which generates the data concerning digitalinformation carrier consisting of a plurality of image objects accordingto the data inputted into the input device and outputs to the outputdevice, and is characterized by having a conversion step for convertingthe inputted data into bit data and a generation step for identifying atleast two image objects correlating to the bit data converted by theconversion means and the relative relationship of these and forgenerating the image data of a cluster information carrier whichconsists of at least two image objects based on the specified contents.

It is realized by performing the method concerned to output from theoutput device a digital information carrier which contains clusterinformation carrier and can avoid incorrect recognition.

Method for creating a digital information carrier concerning the 27thaspect of this invention offered in order to solve the above-mentionedproblems is the method for creating digital information carrier relatedto the 26th aspect of this invention, and when the amount of the bitdata obtained by the conversion means is bigger than the maximum amountof data which one cluster information carrier can display, the bit dataafter conversion is converted into a bit arrangement which uses bit datawith a data size below the maximum amount of data as an element by theconversion step, and by the generation step, while image data of aplurality of cluster information carriers are generated to correlate tothe bit data which serve as each element of the bit arrangement, thedisplay position of a plurality of the image data is determined tocorrelate to the arrangement relationship of the bit arrangement.

By performing the method concerned, a plurality of cluster informationcarriers are outputted from the output device so that a bit arrangementcan be formed from the relative position of those. For this reason, itis realized to generate data with a size bigger than the maximum amountof data which one cluster information carrier can display by recognizingthe relative arrangement of a plurality of cluster information carriersas decoded information.

Method for creating digital information carrier concerning the 28thaspect of this invention offered in order to solve the above-mentionedproblems is the system for creating digital information carrier relatedto the 26th or 27th aspect of this invention, and the processing deviceis equipped with an input/output part which exchanges a data signal withthe input device and the output device, a processing part whichprocesses the data inputted from the input/output part, and a memorypart which records the data required in order for the processing part tocarry out data processing, the memory part has image data of the clusterinformation carrier and correspondence relationship data concerning thecorrespondence relationship between the cluster information carrier andthe bit data, and the generation step comprises a step for selectingcluster information carriers correlating to the bit data converted bythe conversion step based on the correspondence relationship data storedin the memory part, a reading step for reading the image datacorrelating to the selected cluster information carriers from the memorypart, and a determination step for determining the display position ofthe image data of the read cluster information carriers.

By performing the method concerned, it is realized to form a clusterinformation carrier which displays the inputted data by having theprocessing part suitably exchanging data with the memory part.

System for generation of decoded information for the digital informationcarrier related to the 29th aspect of this invention offered in order tosolve the above-mentioned problems is equipped with an input device forinputting digital information carrier which consists of a plurality ofimage objects, a processing for generation of the decoded informationwhich the inputted digital information carrier holds, and an outputdevice which outputs the decoded information, and the processing deviceis characterized by recognition means for recognizing the digitalinformation carrier inputted from the input device as a plurality ofimage objects, a cluster judging means for determining whether one of aplurality of the image objects makes a group with any other image objectand constitutes a cluster information carrier, and a decoded informationgeneration means for decoding bit data from the judged clusterinformation carrier given that it is judged to constitute a clusterinformation carrier and for generating decoded information based on thebit data.

By the system concerned, it is realized to carry out processing, such asdecoding, etc., to the digital information carrier which containscluster information carrier inputted from the input device whilesuppressing the possibility of occurrence of incorrect recognition inthe processing device, to generate decoded information having a lowpossibility of containing incorrect information as a result of theprocessing, and to have the decoded information outputted from theoutput device.

System for generation of decoded information for digital informationcarrier related to the 30th aspect of this invention offered in order tosolve the above-mentioned problems is the system for generation ofdecoded information for the digital information carrier related to the29th aspect of this invention, and when there is a plurality of clusterinformation carriers determined by the cluster judging means, aplurality of bit data is generated by decoding a plurality of thecluster information carriers, some of the plurality of the bit data isunified to form a bit arrangement based on the relative arrangement ofthe plurality of the cluster information carriers, and unit informationis generated as decoded information from the bit arrangement by themeans for generation of decoded information.

According to the system concerned, unit information distributed andretained by a plurality of cluster information carriers can begenerated. For this reason, it is realized to have a bigger amount ofdata than the maximum amount of data which one cluster informationcarrier can display, been displayed on digital information carrier.

In addition, although the method for unifying bit data based on therelative arrangement may be set beforehand, the optimal unifying methodmay be determined in the process for generating the decoded informationby this system.

System for generation of decoded information for digital informationcarrier related to the 31st aspect of this invention offered in order tosolve the above-mentioned problems is the system for generation ofdecoded information for the digital information carrier related to the29th or 30th aspect of this invention, the processing device has aprocessing part which handles data processing and a memory part whichrecords data required for data processing, and with the cluster judgingmeans, the relative relationship of a plurality of image objects servesas a judgment condition and this condition is stored in the memory part.

A ghost dot integrated without having a relative relationship with otherimage objects is eliminated effectively by adopting the judgmentcondition concerned. Therefore, a system that can avoid incorrectrecognition is realized.

System for generation of decoded information for digital informationcarrier related to the 32nd aspect of this invention offered in order tosolve the above-mentioned problems is the system for generation ofdecoded information for digital information carrier concerning the 31staspect of this invention, and cluster information carrier that has bitdata correlating to the relative relationship of a plurality of imageobjects which are its constituent elements, the memory part has thecorrespondence relationship data between the relative relationship andbit data, and means for generation of decoded information includedecoding means for decoding bit data from cluster information carrierbased on the correspondence relationship data stored in the memory part.

Even if there is a cluster information carrier which contains a ghostdot as a constituent element by incorrect recognition, since bit data iscorrelated to the relative relationship of a plurality of image objects,the possibility of bit data being decoded is low. Therefore, mistakenlydecoded information is not likely to be generated. In addition, since itis possible to have many data bits correlated to one cluster informationcarrier, large scale carriers and improvement in display density of thedigital information carrier are realized.

System for generation of decoded information for digital informationcarrier related to the 33rd aspect of this invention offered in order tosolve the above-mentioned problems is the system for generation ofdecoded information for digital information carrier concerning one ofthe 29th-32nd inventions of this application, and is equipped withjudging means of image quality for evaluating how much the display stateof a plurality of image objects constituting cluster informationcarriers judged by the cluster judging means is out of alignment fromthe ideal display state of the cluster information carriers and forjudging whether it would be decoded by the means for generation ofdecoded information based on the result of the evaluation.

Display state here refers to shape distortion, color deviance, etc., andthe reasons for this display state being out of alignment from the idealdisplay state can attributed to the processing of digital informationcarrier in the output device (for example, scanning gap of a printer),the reasons attributed to the input state in the input device (forexample, a large tilt angle of a camera), the reasons attributed to theprocessing in the input device (for example, low contrast and no colordifference).

The system concerned evaluates the gap from the ideal display state ascluster information carrier by a plurality of image objects. For thisreason, it is possible to set better evaluation criteria compared withthe case where evaluation is per image object, thus evaluation accuracyimproves. In addition, this is effective for improvement in evaluationaccuracy when display area is also large, and this is important when theobject of evaluation has image distortion. Furthermore, when the samecontent as the judgment conditions (cluster function) for judgingwhether it constitutes cluster information carrier is the object ofevaluation, quantifying the sufficiency rate of the judgment conditionscan be used as an evaluation threshold of the gap, and thus highevaluation accuracy is realized.

In addition, in the system concerned, when the evaluation result of thegap is bad, it is directed not to consider the cluster informationcarrier as a decoding object. It is because the possibility of producingincorrect recognition is still high, even if it is judged to constitutea cluster information carrier in the judgment of whether to constitutecluster information carriers, that is, the cluster function. For thisreason, the system in which incorrect recognition is especially notlikely to occur can be easily is realized.

System for generation of decoded information for digital informationcarrier related to the 34th aspect of this invention offered in order tosolve the above-mentioned problems is the system for generation ofdecoded information for the digital information carrier performed by aprocessing device which generates decoded information obtained byprocessing the digital information carrier inputted into the inputdevice inputting digital information carrier which consists of aplurality of image objects and which outputs the decoded information,and the processing device is characterized by being equipped with arecognition step for recognizing the digital information carrierinputted from the input device as a plurality of image objects, acluster judging step for determining whether one of a plurality of theimage objects groups with any other image object and constitutes acluster information carrier, and a step for decoding bit data from thejudged cluster information carrier given that it is judged to constitutea cluster information carrier and for generating decoded informationbased on the bit data.

By adopting the method concerned, it is realized to carry outprocessing, such as decoding, etc., to the digital information carrierwhich contains cluster information carrier inputted from the inputdevice while suppressing the possibility of occurrence of incorrectrecognition in the processing device, to generate decoded informationhaving a low possibility of containing incorrect information as a resultof the processing, and to have the decoded information outputted fromthe output device.

Method for generation of decoded information for digital informationcarrier related to the 35th aspect of this invention offered in order tosolve the above-mentioned problems is the method for generation ofdecoded information for the digital information carrier concerning the34th aspect of this invention, and when there is a plurality of clusterinformation carriers judged by the cluster judging step, plurality ofbit data is generated by decoding a plurality of the cluster informationcarriers, some of a plurality of the bit data is unified to form a bitarrangement based on the relative arrangement of a plurality of thecluster information carriers, and unit information is generated asdecoded information from the bit arrangement by the decoded informationgeneration step.

By adopting the method concerned, one information distributed andretained by a plurality of cluster information carriers is generated.For this reason, it is realized to have bigger amount of data than themaximum amount of data which one cluster information carrier candisplay, been displayed on digital information carrier.

In addition, although the method for unifying bit data based on therelative arrangement may be set beforehand, the optimal unifying methodmay be determined in the process for generating the decoded informationby this system.

Method for generation of decoded information for digital informationcarrier related to the 36th aspect of this invention offered in order tosolve the above-mentioned problems is the method for generation ofdecoded information for the digital information carrier concerning the34th or 35th aspect of this invention, the processing device has theprocessing part which handles data processing and the memory part whichrecords data required for data processing by the processing part, and atthe cluster judging step, the relative relationship of a plurality ofimage objects serves as the judgment condition and this judgmentcondition is stored in the memory part.

The ghost dot integrated without having a relative relationship withother image objects is eliminated effectively by adopting the judgmentcondition concerned. Therefore, the system with which incorrectrecognition does not easily take place is realized.

Method for generation of decoded information for digital informationcarrier related to the 37th aspect of this invention offered in order tosolve the above-mentioned problems is the method for generation ofdecoded information for the digital information carrier concerning the36th aspect of this invention, and cluster information carrier that hasbit data correlating to the relative relationship of a plurality ofimage objects which are its constituent elements, the memory part hasthe correspondence relationship data concerning the correspondencerelationship between the relative relationship and bit data, and adecoded information generation step includes a decoding step fordecoding bit data from cluster information carrier based on thecorrespondence relationship data stored in the memory part.

Even if there is a cluster information carrier which contains a ghostdot as a constituent element by incorrect recognition, by bit data beingcorrelating to the relative relationship of a plurality of imageobjects, a possibility of bit data being decoded becomes low. Therefore,the mistakenly decoded information is not likely to be generated. Inaddition, since it is realized to have many bit data correlated to onecluster information carrier, the improvement in display density ofdigital information carrier and making it larger-scaled are realized.

Method for generation of decoded information for digital informationcarrier related to the 38th aspect of this invention offered in order tosolve the above-mentioned problems is the method for generation ofdecoded information for the digital information carrier concerning oneof the 34th-37th aspects of this invention, and is equipped with adisplay state judging step for evaluating how much the display state ofa plurality of image objects constituting cluster information carriersjudged by the cluster judging step is out of alignment from the idealdisplay state of the cluster information carriers and for judgingwhether it would be decoded by the generation of decoded informationstep based on the result of the evaluation.

The method concerned evaluates the gap from the ideal display state ascluster information carrier by a plurality of image objects. For thisreason, it is possible to set better evaluation criteria compared withthe case where evaluation is per image object, thus evaluation accuracyimproves. In addition, this is effective for evaluation accuracyimprovement when the display area is also large, and this is importantwhen the object of evaluation has image distortion. Furthermore, whenthe same contents as the judgment conditions (cluster function) forjudging whether it constitutes cluster information carrier is the objectof evaluation, quantifying the sufficiency rate of the judgmentconditions can be used as an evaluation threshold of the gap, and thushigh evaluation accuracy is realized.

In addition, by the method concerned, when the evaluation result of thegap is bad, it is directed not to consider the cluster informationcarrier as decoding object. It is because the possibility of producingincorrect recognition is still high, even if it is judged to constitutea cluster information carrier in the judgment of whether to constitutecluster information carriers, that is, the cluster function For thisreason, the system in which incorrect recognition is especially notlikely to occur can be easily is realized.

Program related to the 39th aspect of this invention offered in order tosolve the above-mentioned problems is a program for having a computerperform the method for creating digital information carrier concerningthe 26th or 28th aspect of this invention.

Program related to the 40th aspect of this invention offered in order tosolve the above-mentioned problems is a program for having a computerperform the method for generation of decoded information for digitalinformation carrier concerning one of the 34th-38th inventions of thisapplication.

Recording medium related to the 41st aspect of this invention offered inorder to solve the above-mentioned problems is a recording medium whichhas recorded the program for having a computer perform the method forcreating digital information carrier concerning the 26th or 28th aspectof this invention with computer reading possible.

Recording medium related to the 42nd aspect of this invention offered inorder to solve the above-mentioned problems is a recording medium whichhas recorded the program for having a computer perform the method forgeneration of decoded information for digital information carrierconcerning one of the 34th-38th inventions of this application withcomputer reading possible.

Effect of the Invention

According to one of the modes of this invention, digital informationcarrier contains cluster information carrier which has bit datacorrelating to the relative relationship of a plurality of imageobjects. This cluster information carrier can hold more bit data ratherthan the case where bit data is correlated to each of the constituentsof the plurality of image objects. For this reason, the number ofconstituent image objects of digital information carrier decreases, andlowering the display density of an image is realized. Therefore, theinfluence of ghost dots etc. decreases, false recognition becomesunlikely and digital information carrier that is easy to display and hasa fast recognition speed is realized. In addition, high positionresolution can be achieved for the digital information, since many databits can be displayed on a few image display regions.

In addition, according to another mode of this invention, judgment onwhether one image object which is a constituent element of digitalinformation carrier constitutes a cluster information carrier with otherimage objects is performed, and decoding is performed only when it isjudged to constitute a cluster information carrier in this judgment. Forthis reason, it is easy to identify a ghost dot displayed because it isalmost irrelevant to other image objects. Therefore, a digitalinformation carrier with which incorrect recognition does not easilytake place is realized.

In addition, according to yet another mode of this invention,information is also given to the relative arrangement of clusterinformation carrier. Since cluster information carriers are not easilyinfluenced by ghost dots as mentioned above, the information containedin the relative arrangement of the cluster information carriers is noteasily influenced by the ghost dots either. Therefore, digitalinformation carrier with which incorrect recognition does not easilytake place is realized. In addition, since the information which thecluster information carrier has and the information which the relativearrangement has are essentially independent, digital informationcarriers which have mutually independent information and digitalinformation carrier with which unit information is generated byassociating mutual information are realized. For this reason, theinformation retention mode of the whole digital information carrierincreases.

Therefore, digital information carrier wherein information retentiondensity and the possibility of incorrect recognition are adjustedaccording to the display mode or the usage can be created.

In addition, according to yet another mode of this invention, a newlogical block (virtual block) can be constituted by replacing at leastone of the constituent elements of the logical block (virtual block)formed by unifying a plurality of unit information carriers which arethe minimum unit at the time of decoding a digital information carrierwith a unit information carrier adjacent to the logical block (virtualblock). Unlike the logical block by prior art wherein the block form wasfixed in the shape of a matrix, the new logical block (virtual block)formed by replacement this way has a high form flexibility of the block.For this reason, even if some unit information carriers recognized asimage are not suitable for decoding, a logical block (virtual block) canbe easily constituted so that it does not contain these. Therefore, adigital information carrier for which the possibility of non-recognitionor of incorrect recognition is very low is realized. In addition, therange needed as a recognition range becomes narrower in comparison tothe case of adopting a logical block from prior art wherein the blockform was fixed, and therefore it becomes possible to set fewer clusterinformation carriers in the recognition range. Therefore, imageprocessing needed for position recognition can be performed in a shortertime.

BRIEF DESCRIPTION OF DRAWINGS

[FIG. 1] The figure shows an example of a cluster information carrierwhich consists of one dot and one line segment.

[FIG. 2] The flowchart shows an example of operation of the clusterfunction for judging the cluster information carrier shown in FIG. 1.

[FIG. 3] The figure shows an example of the arrangement of clusterinformation carrier shown in FIG. 1.

[FIG. 4] The figure conceptually shows the relationship of the numericalvalue converted reference bit arrangement and the partial arrangementhaving an arrangement length of 4 obtained by suitably offsetting thereference bit arrangement into the decimal system and the offset value.

[FIG. 5] The flow chart shows the outline of the processing for derivingan offset value from the partial arrangement having an arrangementlength of 4.

[FIG. 6] The figure shows an example which expresses 2-dimensions usinga 1-dimensional arrangement.

[FIG. 7] The figure shows an example of a digital information carriercoded under the rule related to FIGS. 1 and 4 using the expressionmethod of FIG. 6.

[FIG. 8] The figure shows an example where a plurality of 1-dimensionalarrangements in the X-axis direction formed by arranging digitalinformation carriers coded under the rule related to FIGS. 1 and 4, arearranged in the Y-axis direction.

[FIG. 9] The figure shows an example of a plurality of 1-dimensionalarrangements in the Y-axis direction formed by arranging digitalinformation carriers coded under the rule related to FIGS. 1 and 4 arearranged in the X-axis direction in the digital information carrier ofFIG. 8.

[FIG. 10] The figure shows an example of cluster information carrierwhich can have information worth 2 bits.

[FIG. 11] The figure shows an example of a digital information carrierformed by arranging cluster information carriers shown in FIG. 10 in2-dimensions based on the rule of FIG. 4.

[FIG. 12] The figure shows an example of a cluster information carrierhaving high symmetry of the form and having a maximum of 1-bit ofinformation.

[FIG. 13] The figure shows an example of a cluster information carrierhaving high symmetry of the form and having a maximum of 2-bits ofinformation.

[FIG. 14] The figure shows an example of a cluster information carrierhaving high symmetry of the form and having a maximum of 2-bits ofinformation.

[FIG. 15] The figure shows an example of a cluster information carrierhaving high symmetry of the form and having a maximum of 2-bits ofinformation. is shown.

[FIG. 16] The figure shows an example of digital information carrierformed by arranging cluster information carriers specified in FIG. 15 ona plane.

[FIG. 17] The figure shows an example of digital information carrierwherein two sorts of cluster information carrier shown in FIGS. 14 and15 are used together.

[FIG. 18] The figure shows an example which makes the image objectsconstituting a cluster information carrier mutually different only bythe size.

[FIG. 19] The figure shows an example of the rule for decoding thecluster information carrier concerning FIG. 18.

[FIG. 20] The figure shows an example of a rule for decoding a maximumof 2-bits of information from the cluster information carrier related toFIG. 18.

[FIG. 21] The figure shows an example of a rule for decoding a maximumof 4-bits of information from the cluster information carrier related toFIG. 18.

[FIG. 22] The figure shows an example of cluster information carrierwhich consists of one to four dots.

[FIG. 23] The figure shows an example of cluster information carrierformed by coding bit data in the form of the cluster informationcarrier.

[FIG. 24] The figure shows an example of digital information carrierwherein the information for identifying the coordinate axis is containedin the arrangement interval of the cluster information.

[FIG. 25] The figure shows an example of the virtual block concerningthe invention of this application.

[FIG. 26] The figure shows an example of the virtual block to which formflexibility is given.

[FIG. 27] In this figure a virtual block and a recognition range aredisplayed on an example of the bit matrix formed by decoding digitalinformation carrier.

[FIG. 28] In this figure a virtual block and a matrix element that canbe mutually replaced with the recognition range are displayed on anexample of the bit matrix formed by decoding digital informationcarrier.

[FIG. 29] The figure shows an example of digital information carrierwhich uses cluster information carrier having high symmetry and does nothave directional dependency in the cluster information carrier interval.

[FIG. 30] The figure shows another example of the virtual blockconcerning the invention of this application.

[FIG. 31] The figure shows an arrangement wherein cluster informationcarriers surrounded with a rectangle or a circle are arranged out ofalignment a little downward than other cluster information carriers forthe digital information carrier shown in FIG. 29.

[FIG. 32] This is a conceptual figure of the digital information carriergeneration system 11 concerning this invention.

[FIG. 33] This is a flow chart conceptually showing an example ofoperation of the digital information carrier generation system 11.

[FIG. 34-1] This is a conceptual figure for explaining operation (firsthalf) of the digital information carrier generation system 11.

[FIG. 34-2] This is a conceptual figure for explaining operation (secondhalf) of the digital information carrier generation system 11.

[FIG. 35] This is a conceptual figure of the digital information carrierdecoding system 21 concerning this invention.

[FIG. 36-1] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (firsthalf, part 1).

[FIG. 36-2] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (firsthalf, part 2).

[FIG. 36-3] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (firsthalf, part 3).

[FIG. 37-1] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (secondhalf, part 1).

[FIG. 37-2] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (secondhalf, part 2).

[FIG. 37-3] This is a flow chart conceptually showing an example ofoperation of the digital information carrier decoding system 21 (secondhalf, part 3).

[FIG. 38] This is a figure conceptually showing an example of processingconcerning the logical block.

[FIG. 39] This is a figure conceptually showing another example ofprocessing concerning the logical block.

DESCRIPTION OF THE NOTATION(S)

11: Digital information carrier generation system

101: Input device

102: Processing device

102 a: Input/output part

102 b: Processing part

102 c: Memory part

103: Output device

111: Paper-like medium

112: Paper-like medium

21: Digital information carrier decoding system

201: Input device

202: Processing device

202 a: Input/output part

202 b: Processing part

202 c: Memory part

203: Output device

MODES FOR CARRYING OUT THE INVENTION

The digital information carrier concerning this invention is explainedin detail hereafter.

A dot and a line segment can be mentioned as the simplest image objects.Therefore, in order to make understanding easy, these are used asexamples also in the explanation of cluster information carrierconcerning the invention of this application.

FIG. 1 is the figure showing an example of cluster information carrierwhich consists of one dot and one line segment, and FIG. 2 is the flowchart showing an example of the operation of the cluster function forjudging a cluster information carrier shown in FIG. 1.

A cluster information carrier as shown in FIG. 1 which consist of onedot and one line segment and a cluster function as shown in FIG. 2 areexamined.

Each image object is recognized using a very general image-processingmethod, and the principal diameters and the center of gravity of theobject are calculated. When the principal diameters are the same, theimage object is a circle, that is, a dot, and when there is sufficientdifference in the principal diameters, it is recognized as being a linesegment.

With this cluster function, input parameters are two image objects obj1and obj2, and an output value is a TRUE or a FALSE value.

Suppose that by definition only two different image objects, that is, adot and a line segment, are contained in one cluster information carrierhere. Therefore, when calculating the principal diameters for each ofthe inputted obj1 and obj2 (Step S301), it can be determined whether theobject is a dot or a line segment, respectively.

Then, for the two concerned image objects, under consideration forconstituting or not a cluster information carrier, it is determinedwhether they are of the same kind (a dot and a dot, or a line segmentand a line segment) (Step S302).

If they are found to be of the same kind at Step S302, it is determinedby the clustering function that these image objects do not constitute acluster information carrier, and a FALSE value is outputted.

On the other hand, when they are determined not to be of the same kindat Step S302, the distance between the centers of gravity is calculatedfor the two image objects (Step S303), and this distance is comparedwith the threshold specified beforehand.

Then, a judgment whether the distance between the centers of gravity ofthe two image objects of different type, that is, a dot and a linesegment, is closer than the threshold is made (Step S304).

When it is judged that this distance is closer than the threshold atStep S304, these image objects are judged by the cluster function thatthey constitute a cluster information carrier, and a TRUE value isoutputted. On the other hand, a FALSE value is outputted when it isjudged that they are further apart than the threshold.

According to the cluster function as shown in FIG. 2, when the imageobjects concerning the judgment processing satisfy the definition ofclustering, it is judged to constitute cluster information carrier.

Here, besides the authenticity judging, specific processing of ajudgment may be performed based on the display distortion value as acluster, in other words, the measured value obtained by measuring theerror rate value for the cluster information carrier.

This measured rate value quantitatively shows how close the clusterinformation carrier concerning the present judgment processing is to theideal cluster information carrier by the definition of clustering. Ifcluster information carrier shown in FIG. 1 is used as an example, theratio of the longest among the principal diameters (the longestprincipal diameter) P in the dot contained in one cluster informationcarrier and the longest among the principal diameters S in the linesegment must be close to 1/3. When the longest principal diameter ratioof the dot and the line segment shifts away from 1 and comes closer to1/3, the numerical value of P/S-1/3 comes closer to zero. In addition,the condition may be set so that the distance D between the center ofgravity of the dot and the line segment must be smaller than S/2. Whenthe dot and the line segment are arranged in a mutually suitableposition at this time, the numerical value of D−S/2 comes closer tozero. These two expression formulas may be combined, and the sum of thetwo absolute values may be used as a measure value of the displaydistortion for judging whether to constitute a cluster informationcarrier. Specifically, it can be judged to constitute clusterinformation carrier on the condition that the measure value is smallerthan the predetermined threshold. In addition, although a very simpleexample was shown as a calculation method of display distortion in orderto make understanding easy here, the invention of this application isnot restricted to the above-mentioned content, and distortioncalculation may be carried out using other methods. The obtainedmeasurement value of display distortion is used also in decoding ofdigital information carrier as mentioned later.

Once cluster information carrier is recognized, encoded bit data isdecoded as follows.

First, the center-of-gravity position of the line segment belonging to acluster information carrier is set as the center of the clusterinformation carrier, and image processing is performed so that thecenter is moved to the origin for decoding processing.

Next, rotation processing of the image is performed for the clusterinformation carrier so that the line segment belonging to clusterinformation carrier is arranged on the X-axis.

Then, the coordinates in the coordinate system which uses the center ofgravity of the line segment as an origin are derived for the dotbelonging to the cluster information carrier. When the X coordinatevalue and the Y coordinate value of the dot are the same, it is decodedto “1”, and when the X coordinate value differs from the Y coordinatevalue, it is decoded to “0.”

In addition, decoding processing may be performed without performing theconversion processing of the above-mentioned cluster informationcarriers substantially but only by doing the confirmation work ofcoordinates, and then a recognition system can be realized at lowcomputational cost in this case.

An example of an arrangement of the cluster information carriers shownin FIG. 1 is shown in FIG. 3. In this case, the decoded bit arrangementis “101000.” Here, in decoding this cluster information carrierarrangement, since each cluster information carrier has asymmetricalform regarding 180-degree rotations, the first cluster informationcarrier of the arrangement is determined unambiguously. For this reason,a bit arrangement in a reverse order (like “000101”) can not bemistakenly obtained. Therefore, asymmetrical cluster information carrierarrangement can be directly used for linear coding, and the coordinaterange is regulated only by the length of the bit arrangement at thistime.

Next, linear coding which generates unit information from this bitarrangement is explained using FIG. 4.

FIG. 4 is the figure conceptually showing the relationship of thenumerical value converted reference bit arrangement and the partialarrangement having an arrangement length of 4 obtained by suitablyoffsetting the reference bit arrangement into the decimal system and theoffset value.

Here, priority is given to the ease of understanding, and theexplanation is given using a reference bit arrangement having anarrangement length of only 15 as shown in FIG. 4.

If the reference bit arrangement which consists of 15 bits shown in FIG.4 is selected with arbitrary consecutive 4 bits as a partialarrangement, 15 partial arrangements of those other than “0000” can beobtained. For offset 0, the partial arrangement is “0001” which is “1”in the decimal system. Similarly, for offset 1, the partial arrangementis “0011” which is “3” in the decimal system, and for offset 2, thepartial arrangement is “0111” which is “7” in the decimal system. Inaddition, since this reference bit arrangement is of a circular type,the bit after the 15th bit returns to the beginning of the arrangement.The partial arrangement which uses the 13th to the 15th bit as astarting point is actually obtained by appending the first three bits ofthe arrangement, that is, “000”, to the end of the arrangement. Forexample, for offset 14, the partial arrangement is “1000” which is “8”in the decimal system.

Here, it should be noted that there is no overlapping arrangement in the15 partial arrangements selected from the reference bit arrangement. Forthis reason, the positional information of the 15 coordinate values canbe coded with the offset value from the 1st bit of the reference bitarrangement having the arrangement length of 15.

The derivation of an offset value is explained in detail using FIG. 5.The flow chart shows the outline of the processing for deriving anoffset value from the partial arrangement having an arrangement lengthof 4.

First, “0” is set as an offset value of the initial stage for extractinga partial arrangement from the reference bit arrangement (Step S320).Then, the partial arrangement having an arrangement length of 4 whichuses the offset value as a starting point is generated (Step S321).

The partial arrangement is compared with the bit arrangement having thearrangement length of 4 and provided as a parameter for processing (StepS322), and when it is judged to be the same, the offset value isoutputted and the processing concerning FIG. 5 is finished.

On the other hand, when it is judged not to be the same, the offsetvalue is increased by “1” (Step S323), and the offset value after theincrease is checked whether it is smaller than 14 (Step S324). If it issmaller, it moves on to Step S321 and the processing after generation ofthe partial arrangement is performed.

On the other hand, when it not smaller than 14 at Step S324, it meansthat the partial arrangement which uses any of the offset values as thestarting point is not the same as the bit arrangement concerning theprocessing. Therefore, an error value (for example, −1) is outputted andthe processing concerning FIG. 5 is finished.

This is illustrated still in more detail below. If four consecutivecluster information carriers are recognized during the image recognitionof the predetermined range of digital information carrier, thepositional information is acquired from the bit arrangement obtained bydecoding them. For example, if the bit arrangement is “1101”, since thenumerical value in the decimal system is “13”, the offset value will be“5”, and it will be determined that the coordinate of the recognitionrange is “5.” The bit arrangement having the bit length shown here isjust an illustration, and the method related to this invention can beapplied without device dependency to bit arrangement having an arbitrarybit lengths.

The 1-dimensional bit arrangement obtained by the above-mentioneddecoding of digital information carrier to which linear coding wasapplied is easily extended into 2-dimension. This extension is explainedusing FIG. 6 and FIG. 7.

FIG. 6 is the figure showing an example which expresses 2-dimensionsusing a 1-dimensional arrangement.

FIG. 7 is the figure showing an example of digital information carriercoded under the rule concerning FIGS. 1 and 4 using the expressionmethod of FIG. 6.

For example, all positions in 2-dimentions can be identified byassigning numbers to the entire surface by the method shown in FIG. 6.An example which actually encodes the upper left triangular region inFIG. 6 is shown in FIG. 7. Note that the triangular region in FIG. 7 isrotated by 45 degrees to the right for convenience.

There is a method for expressing 1-dimension by one digital informationcarrier and using two such digital information carriers as anothermethod for expressing 2-dimension. This other method is explained usingFIG. 8 and FIG. 9.

FIG. 8 is the figure showing an example wherein a plurality of1-dimensional arrangements formed by arranging digital informationcarriers coded under the rule concerning FIGS. 1 and 4 in the X-axisdirection are arranged in the Y-axis direction.

FIG. 9 is the figure showing an example wherein a plurality of1-dimensional arrangements formed by arranging digital informationcarriers coded under the rule concerning FIGS. 1 and 4 in the Y-axisdirection are arranged in the X-axis direction in the digitalinformation carrier of FIG. 8.

As shown in FIG. 8, 1-dimensional digital information carriers arearranged in a plurality of rows with a predetermined interval. Next, thedigital information carrier is rotated by 90 degrees, and the same1-dimensional digital information carriers are further arranged. Thisway, the digital information carrier as shown in FIG. 9 is obtained.

With this digital information carrier, it becomes possible by decodingtwo sorts of codes independently to regulate every position on thesurface. For example, the bit arrangement formed by decoding fourcluster information carriers surrounded by the horizontally elongatedrectangle is “0111”, and its offset value “2” shows the X coordinatevalue. Similarly, the bit arrangement formed by decoding four clusterinformation carriers surrounded by the vertically elongated rectangle is“0011”, and its offset value “1” shows the Y coordinate value. Once thedirection (which is the positive direction) of the bit arrangement isrecognized here, attribution of each axis will be easily performed fromthe relationship of the positive direction of two axes of coordinates, Xand Y

When cluster information carrier can have information worth of 2 bits orcan have four different numerical values, it also becomes possible forone cluster information carrier to have 2-dimensional informationdirectly. An example is shown in FIG. 10 and FIG. 11.

FIG. 10 is the figure showing an example of cluster information carrierwhich can have the information worth of 2 bits.

FIG. 11 is the figure showing an example of digital information carrierformed by arranging cluster information carriers shown in FIG. 10 in2-dimensions based on the rule of FIG. 4.

In the cluster information carrier shown as an example here, two linesegments which form one image object show the X-axis and the Y-axiswhich intersect at the origin. Decoding of the cluster informationcarrier is performed by recognizing the coordinate of the dot in thecoordinate system by this X-axis and Y-axis. In this example, the X(Y)coordinate value is “0” when the numerical value which shows coordinateby focusing on the Y (X) coordinates is negative, and decoding isperformed as “1” in the case where it is positive. An example of adigital information carrier coded by this method is shown in FIG. 11.

An example of decoding the positional information in this region isshown. At the place where four consecutive cluster information carriershorizontally surrounded in FIG. 11 are selected, when the bit data whichis obtained by decoding each cluster information carrier are unified,two 4-bit arrangements in the X-axis direction and the Y-axis directionare acquired. The bit arrangement showing the X-axis direction is“0001”, and the bit arrangement showing the Y-axis direction is “1111.”If an offset value is calculated for these bit arrangements based onFIG. 5, “0” will be obtained for the X-axis direction, and it will berecognized as the X coordinate value being “0.”

On the other hand, it should be noted that the offset value of theY-axis direction cannot be used for showing the coordinate value of theY-axis direction.

For this reason, in order to acquire the Y coordinate value, clusterinformation carriers of four consecutive in the vertical direction withthe first cluster information carrier of the four cluster informationcarriers consecutive in the horizontal direction mentioned above as thehead is selected, and two bit arrangements are obtained by unifying thebit data obtained by decoding these. In this case, the bit arrangementcorrelating to the coordinate value only from the Y-axis is obtainedcontrary to the case of the X-axis direction. Specifically, as shown inFIG. 11, “1111” is obtained in the Y-axis direction, and “3” is obtainedas the Y coordinate value.

In the case of an asymmetrical cluster information carrier which wasused for the above-mentioned explanation, it is very easy to attributethe X-axis and the Y-axis. On the other hand, the symmetry of theconstituent image object is high and the symmetry as cluster informationcarrier is also high for this reason, although the configuration isrelatively simplified, the coordinate axis may not be easily recognizedfrom the arrangement of its cluster information carrier. In addition,the solution means for the ambiguity about the recognition of thecoordinate system which occurs in cluster information carrier with suchhigh symmetry is explained in detail later.

An example of cluster information carrier with a highly symmetrical formis shown in FIGS. 12-15. An example of cluster information carrier whichcan contain 1-bit information formed by using two image objects of dotform is shown in FIG. 12. An example of cluster information carrierwhich can contain 2-bit information formed by using the same two dotforms is shown in FIG. 13. Examples of cluster information carrier whichcan contain 2-bit information formed by using two line segments areshown in FIGS. 14 and 15, respectively. An example of digitalinformation carrier formed by arranging cluster information carriersregulated in FIG. 15 on a plane is shown in FIG. 16.

This digital information carrier shown in FIG. 16 resembles a digitalinformation carrier coded by glyphs at a glance. However, since thedigital information carrier concerning the invention of this applicationis formed based on the principle which completely differs from glyphs asexplained so far, the resemblance on appearance is nothing but simplysuperficial. When carefully examined, it is understood immediately thatthe cluster information carrier concerning this application has not beendisclosed by any prior art.

FIG. 17 is an example of digital information carrier wherein two sortsof cluster information carriers shown in FIGS. 14 and 15 are usedtogether.

In the digital information carrier shown in FIG. 17, the distancebetween the centers of gravity of each constituent image object isconstant, and it is unknown which two image objects constitute a clusterinformation carrier at a glance. However, by using the object sortdetermined by the direction of an image object rather than using thedistance between two image objects for the judgment of whether toconstitute a cluster information carrier, it becomes possible to make ajudgment easily. In reality, in the case of judging using the maximumproximity distance between two image objects, it will be judged that themaximum proximity distance between the image object 17-2 which is in thefirst row of the second column when considering the image object of theupper left corner as the first row of the first column and the imageobject 17-3 adjacent on the right is smaller than the threshold, andwill be judged that these image objects constitute one clusterinformation carrier. However, by judging by the image object sort, theseimage objects will be separated and will be judged that they constitutecluster information carriers with the adjacent image object of the samesort, respectively. Specifically, the image object by the diagonal linesegment shown as image object 17-1 and the image object 17-2 constituteone cluster information carrier, and the image object by the vertical orhorizontal line segment shown as image object 17-3 and the image object17-4 constitutes one cluster information carrier.

The cluster function for performing such a judgment is set so that theminimum angle of the principal axes which make maximum length for eachis calculated for two image objects concerning the judgment. The twoimage objects are recognized to constitute a cluster information carrierwhen the angle is close to 0 degree or 90 degrees. If this is explainedin detail using FIG. 17, the angle of the principal axes which makemaximum length for each of the two image objects 17-1 and 17-2 is closeto 0 degree and the two line segments are almost parallel, and the angleof the principal axes which make maximum length for each of the twoimage objects 17-3 and 17-4 is close to 90 degrees and the two linesegments intersect almost perpendicularly. On the other hand, with imageobjects of a different sort, for example, the image objects 17-2 and17-3, the angle becomes about 45 degrees.

In addition, in the digital information carrier shown in FIG. 17, allthe image objects adjacent in the vertical direction are of differentsorts, and it has a configuration in which only the image objectsadjacent in the horizontal direction can form a cluster informationcarrier. It can be said that such a configuration is an importantconfiguration in that the horizontal axis and the vertical axis can bejudged easily based on the direction of the cluster information carrier.

The image objects which constitute cluster information carrier may bemade mutually different only by the size. An example is shown in FIG.18.

FIG. 18 is the figure showing an example which makes the image objectsconstituting a cluster information carrier mutually different only bythe size.

The digital information carrier shown in FIG. 18 is formed by arrangingcluster information carriers constituted by image objects of the dotform of two different sizes. The cluster function based on the size ofthe dot and the threshold of the distance between dots defines a clusterinformation carrier which consists of two big dots and one small dot asshown in 18-1, 18-2, 18-3 of FIG. 18, etc. In recognition of one clusterinformation carrier, two dots are first sampled one by one from therecognized image. If it is judged that two sampled dots are the smalldot S and the large dot L1, these are judged to belong to one clusterinformation carrier. Next, the cluster function judges about the smalldot S recognized as the first parameter whether it constitutes a clusterinformation carrier between image objects which are different from thelarge dot L1 recognized as the second parameter. When the clusterfunction outputs a TRUE value as a result of the judgment, the dotconcerning the judgment is recognized to be the 2nd big dot L2, and itis judged that one cluster information carrier is constituted by L1, S,and L2.

Here, if the characteristics of the cluster information carrierconcerning FIG. 18 is explained, any one dot can serve as a constituentelement of a plurality of cluster information carriers. That is, asshown in cluster information carrier 18-2 and cluster informationcarriers 18-3, cluster information carriers overlap mutually in part.Many advantages are acquired by permitting overlapping like this. Thenumber of image objects needed in order to display a plurality ofcluster information carriers decreases, and digital information carrierstops standing out on a document. It is important that this overlappingdoes not cause interference in coding of data here. Bit data may becoded in the relative arrangement of the image objects which do notoverlap among the image objects which constitute cluster informationcarriers in order to realize such incoherency. FIG. 19 illustrated this.The arrangement of the small dot S between the big dots L1 and L2 isshown in FIG. 19. It is realized to constitute cluster informationcarrier wherein different numerical values are coded by arranging thesmall dot S in any of the positions shown by small outline circles ofFIG. 19, and when each cluster information carrier is decoded, thenumerical value shown in the circle correlating to the position wherethe small dot S is arranged is acquired.

The decoding method of cluster information carrier shown in FIGS. 18 and19 is explained below.

First, the line segment which connects the centers of gravity of the bigdots L1 and L2 is regulated.

Next, the coordinate of the small dot S are calculated and judgedwhether it is above the line segment, it is almost on the line segment,or it is below the line segment. When it is above the line segment, itis any of 1, 2, or 3 in FIG. 19, when it is almost on the line segment,it is any of 4 or 5 in FIG. 19, and when it is below the line segment,it is any of 6, 7, and 8.

Then, the distance |L1S| between the big dot L1 and the small dot S andthe distance |L2S| between the big dot L2 and the small dot S arecalculated and compared, and it is judged in which column the small dotS is.

Here, the maximum amount of information which can be held by a clusterinformation carrier may be 2 bits or 1 bit instead of 3 bits as shown inFIG. 19. A cluster information carrier which can hold the maximum amountof information of 1 bit is shown in FIG. 20, and a cluster informationcarrier which can hold the maximum amount of information of 2 bits isshown in FIG. 21.

In reality, the digital information carrier shown in FIG. 18 isconstituted by the cluster information carriers shown in FIG. 21, andtwo sorts of cluster information carriers shown in FIG. 21 areseparately used in the direction of the horizontal axis and in thedirection of the vertical axis in FIG. 18. For this reason, attributionof the axis is performed easily. The small dot S of the clusterinformation carriers 18-1 and 18-2 of the direction of the horizontalaxis are arranged based on the arrangement configuration of (b) in FIG.21. On the other hand, the small dot S of the cluster informationcarrier 18-3 of the direction of the vertical axis is arranged based onthe arrangement configuration of (a) in FIG. 21.

In addition, although only the cluster information carriers arranged inthe direction of the horizontal axis are shown in FIGS. 19-21, thecoding in the cluster information carriers of the direction of thevertical axis as shown by the cluster information carrier 18-3 of FIG.18 is the same as that of the coding shown in FIGS. 19-21 only with thedifferent axes of coordinate.

In addition, cluster information carriers which consists of differentnumbers of image objects are also effective, and this is explained usingFIG. 22.

FIG. 22 is the figure showing an example of cluster information carrierwhich consists of one to four dots.

In this example, when cluster information carrier is decoded, thenumerical value of 0 to 3 is acquired correlating to the number ofconstituent dots, and it has 2-bit information as cluster informationcarrier. In this case, since informational decoding is performed basedonly on the number of constituent dots, even if it differs as a displayform, cluster information carrier which shows the same bit data (thenumber of bits) may exist. The example of this is shown in FIG. 22.Although some cluster information carriers shown in the direction of acolumn in FIG. 22 differ in the display form, since they have the samenumber of dots, when decoded, they show the same number of bits. It isonly required for these cluster information carriers that the distancebetween the centers of gravity of each dot is smaller than the thresholdregulated beforehand when a plurality of dots are arranged in the samecluster information carrier, and there are no requirements in the formor the size as cluster information carrier.

In addition, in order to respond to a raster type document display, ineach cluster information carrier shown in FIG. 22, the constituent dotobjects are arranged on the lattice at equal intervals. As a result, thecluster information carrier 22-1 and the cluster information carriers22-2 are mutually distinguished by comparing the distance between thecenter of gravity of the dots.

In addition, coding may be performed based on the form of the clusterinformation carrier, and this is explained using FIG. 23.

FIG. 23 is the figure showing an example of cluster information carrierformed by coding bit data in the form of the cluster informationcarrier.

For example, as shown in FIG. 23, three dots may be classified into twogroups based on whether the form formed by arranging them is a straightline or not. In the cluster information carrier shown in FIG. 23, thenumber of dots are 1 and 2 or 3, and decoding is performed based on thenumber of constituent dot objects and the form as cluster informationcarrier. Especially when number of dot objects is 3, the numerical valueacquired by decoding is “2” in the case where the line which connectsthe three dots is a straight line, and it is decoded as “3” in the casewhere it is not a straight line. Here, like the cluster informationcarriers shown in FIG. 22, it should be noted that cluster informationcarriers which have the same information is obtained even if those aredifferent in appearance, in spite of carrying out the judgment based onthe form.

It is very important for a visually different display form to beselected with a certain amount of flexibility while having the sameinformation. It is because it becomes possible to select the dotarrangement of a suitable form so that the appearance as the wholedigital information carrier improves, or to select cluster informationcarriers of a form which gives less sense of incongruity visually to theexisting document display when making bit data integrated to an existingdocument information.

Next, in order to give more detailed explanation of the invention ofthis application, a more practical and relatively simplified example isexplained. A cluster information carrier constituted by having thedistance between the center of gravity of two image objects of dot formwhich have the minimum distance being below the predetermined thresholdis examined. Suppose this cluster information carrier has 2-bitinformation like the one shown in FIG. 13. Like this case, if the imageobject and cluster information carrier are simplified, the symmetry ofthe form of cluster information carrier becomes high. For this reason,it becomes relatively difficult to acquire the information about thecoordinate axis or the direction from the form of cluster informationcarrier.

In such a case, it is desirable to give the information about thecoordinate axis or the direction to the relative arrangement of clusterinformation carrier. Specifically, cluster information carriers may bearranged on a virtual lattice of some sort wherein the lattice intervalis regulated beforehand. This arrangement interval of the clusterinformation carriers, that is, the lattice interval of a virtuallattice, is set to a greater value than the typical distance between thecenter of gravity of the image objects which constitute clusterinformation carrier. In addition, the interval of the direction of a rowand the interval of the direction of a column are set based on differentdefinitions, and it may be made possible to identify a line and a columneasily. When the arrangement interval of the row and the column are setappropriately, even if geometrical modification is performed to theimage recognized in the process of decoding processing, the row and thecolumn are identified easily.

An example is shown in FIG. 24. The figure is showing an example ofdigital information carrier wherein the information for identifying thecoordinate axis for the arrangement interval of cluster informationcarriers is contained. In FIG. 24, the lattice interval of which thevertical direction differs from that of the horizontal direction, thatis, the vertical lattice interval is greater than the horizontal latticeinterval, is applied.

Although how recognition of cluster information carrier is performed hasbeen explained, how cluster information carrier is useful also in thestage of image recognition is explained here.

It is known well that the recognition processing speed of digitalinformation carrier coded in dot form often falls due to the noise andblots on the display called ghost dots. In order to distinguish thisghost dot from a true dot, a virtual lattice of some sort for arrangingimage objects may be used. For example, when a true dot is arranged onthe lattice at a constant interval already regulated, the lattice isrecognized first, and a ghost dot is next distinguished from a true dotby the positional relationship of the lattice and the dot.

However, regulating the lattice interval of this virtual lattice isfacing a very difficult problem. For example, when quite a large numberof ghost dots are contained in a document, recognition of the virtuallattice itself becomes especially difficult. For this reason, exclusionof ghost dots may not be performed appropriately.

On the other hand, by the invention of this application, since thecluster function which judges whether each image object constitutescluster information carrier is applied before decoding, ghost dots areeffectively eliminated in this process.

For example, in image processing, when the image shown in FIG. 24 isrecognized, since the dot which has at least one dot nearby mayconstitute a cluster information carrier, it is classified as a truedot. On the other hand, the dot which has no dot nearby is classified asa ghost dot.

Of course, one ghost dot may exist by chance near the dot whichconstitutes a cluster information carrier. However, the image objectswhich constitute a cluster information carrier in this case becomethree. On the other hand, in the digital information carrier shown inFIG. 24, a cluster information carrier does not consist of three dots.For this reason, it is not recognized that the dots containing the ghostdot constitute a cluster information carrier. And since the clusterfunction regulates the mutual relationship of the dots which constitutea cluster information carrier, by the clustering function, two true dotsare selected from three dots and the ghost dot is eliminated, and anappropriate cluster information carriers may very well be recognized.

In addition, a possibility of finding out a ghost dot in imageprocessing increases by narrowing the true dot interval whichconstitutes cluster information carrier and by increasing the intervalbetween cluster information carriers.

On the other hand, when a cluster information carrier consists ofdifferent image objects, a ghost dot is more efficiently removed inimage processing. For example, in the cluster information carrier shownin FIG. 1, only the dots arranged with a predetermined distance fromboth ends of a line segment can be the true dots. Thus, since therelationship of the image objects which constitute a cluster informationcarrier is regulated beforehand, a ghost dot is easily discovered byusing the relationship. In addition, although a specific mode was usedin the above-mentioned explanation in order to promote understandingabout the use of such a relationship of image objects, these are only anillustration and the invention of this application is not limited by theabove-mentioned explanation.

Return to FIG. 24 again. A cluster information carrier by the dotpattern is shown in FIG. 24 as an example. This dot pattern can hold amaximum of 2 bit per one cluster information carrier, and can bedisplayed on the surface of any sizes. It is shown below that it ispossible to decode the absolute position of the recognition range moreefficiently and to display the digital information carrier concerningthe positional information in the shape of a carpet using this dotpattern according to this invention.

The concept of a virtual block is explained first.

In some prior art, unifying the bit data decoded from a plurality ofimage objects and forming a logical block is disclosed. The logicalblock is effective at the point that it can hold more information thanthe image object itself can. For example, when an image object itselfonly shows 0 and 1, with a logical block formed by unifying ten ofthese, in the case of forming the positional information using theabove-mentioned reference bit arrangement, 210-1 (=1023) positions canbe identified.

The virtual block introduced by the invention of this application isformed by creating a block at a virtual level with a plurality of bitdata formed by decoding the smallest unit (it may be a single imageobject or the above-mentioned cluster information carrier, and may becalled “unit information carrier”) in decoding. Overlapping betweenlogical blocks is permitted by introducing the concept of a virtualblock, control on the level of redundancy is enabled, and recovery isfurther enabled when the image is incorrectly recognized.

Hereafter, the position recognition using a virtual block is explainedin detail using as an example the case where a cluster informationcarriers is selected as the smallest unit (unit information carrier) indecoding. Position recognition shall be performed based on line shapecoding as shown in FIG. 4. That is, a bit arrangement of a predeterminedlength from a virtual block is formed, and by judging which positionthis forms of the partial arrangement for the reference bit arrangement,the positional information shall be acquired by the offset value showingthe starting point of the partial arrangement.

In addition, the size of a virtual block required for positionrecognition is selected as follows. First, the number of coordinatesrequired for position recognition is determined from the size of thedocument on which digital information carrier is displayed and the sizeof cluster information carrier. Next, the number of cluster informationcarriers needed in order to carry out position recognition, that is, thebit arrangement length, is determined from the number of coordinates andthe amount of information which cluster information carrier can hold.Then, the size of a virtual block is determined by taking intoconsideration the display arrangement interval of cluster informationcarriers.

An example of the virtual block concerning the invention of thisapplication is shown in FIG. 25.

A digital information carrier of six rows and eight columns is shown inFIG. 25 as an example. However, in FIG. 25, cluster information carrierwhich is a constituent element is not shown directly, but the bitnumerical value for identifying the coordinate of the X-axis directionand the bit numerical value for identifying the coordinate of the Y-axisdirection from the bit data formed by decoding cluster informationcarrier are calculated, and are equivalent to corresponding arrangementelement of the reference bit arrangement.

If the case where the notation Xm/Yn in the top/bottom of the cell isused, the bit numerical value for the X-axis direction obtained fromcluster information carrier arranged in the correlating position showsthat it is the same as that of the bit numerical value acquired byoffsetting by m the reference bit arrangement (the bit numerical valuewhich serves as the m+1st arrangement element of the bit for referencein other words). In addition, the bit numerical value for the Y-axisdirection shows that it is the same as that of the bit numerical valueacquired by offsetting by n the reference bit arrangement.

Therefore, cluster information carrier concerning FIG. 25 needs to holdthe information which can be distinguished in four ways of (the bitnumerical value for the X-axis direction, the bit numerical value forthe Y-axis direction)=(0, 0), (1, 0), (0, 1), (1, 1), and therefore, itneeds to be the something wherein at least 2 bits can be coded.

In addition, the reason for not directly displaying cluster informationcarrier in FIG. 25 is to make understanding easy.

For this digital information carrier, 12 is selected as the number ofcluster information carriers which constitute a virtual block, and aregion of a shape of a matrix of three rows and four columns is set as avirtual block. In this case, 212 combinations are possible for a virtualblock, and it is possible to form a bit arrangement with an arrangementlength of 12 from this virtual block. In addition, the maximum number ofpositional coordinates which can be identified using this bitarrangement and a suitable arrangement for reference is 212-1. Moreover,if row width and column width of cluster information carrier are set to4:3, the region of three rows and four columns which constitute avirtual block becomes a square.

The bit arrangement with arrangement length of 12 is formed from thevirtual block obtained this way as follows.

For the bit numerical value of the X-axis direction, by using the upperleft end of the virtual block as the starting point, and using theX-axis positive direction to serve as the main scanning direction andthe Y-axis negative direction as the sub-scanning direction, andunifying the bit numerical values of the X-axis direction one by one, abit arrangement with arrangement length of 12 is formed.

On the other hand, for the bit numerical value of the Y-axis direction,by using the upper left end of the virtual block as the starting pointand using the Y-axis negative direction to serve as the main scanningdirection and the X-axis positive direction as the sub-scanningdirection, a bit arrangement with arrangement length of 12 is formedsimilarly.

The bit arrangement obtained this way forms a partial arrangement havingthe arrangement length of 12 in the reference bit arrangement for boththe X-axis direction and the Y-axis direction. In addition, this applieseven if any square region of three rows and four columns in the matrixshown in FIG. 25 is selected to constitute a virtual block.

For example, the bit arrangement of the X-axis direction obtained fromthe virtual block 25-1 shown with a dashed line in FIG. 25 makes thepartial arrangement with the arrangement length of 12 obtained by offset“0” from the reference bit arrangement, and the bit arrangement of theY-axis direction also makes the partial arrangement having thearrangement length of 12 obtained by offset “0” from the reference bitarrangement. In addition, in the virtual block 25-2 shown with a solidline, the bit arrangement of the X-axis direction is the partialarrangement of offset “1”, and the bit arrangement of the Y-axisdirection is the partial arrangement of offset “3.”

This way, the virtual block concerning this invention can be builtregardless of the cluster information carrier used as the startingpoint. Thus, it becomes possible for some virtual blocks to overlap eachother as shown by the virtual block 25-1 (dashed line), 25-2 (solidline), and 25-3 (dotted line) in FIG. 25. This is the point whichdiffers greatly from prior art. In prior art, the block which shows thepositional information constituted on the surface on which digitalinformation carrier is displayed is arranged mainly in the shape oftiles, that is, without overlapping each other, in many cases.

Here, the arrangement of the bit numerical value of each axis of thedigital information carrier in FIG. 25 is explained in a little moredetail. The bit numerical value vx of the X-axis direction of row p andcolumn q and the bit numerical value vy of the Y-axis direction areexpressed as follows, when an upper left end is zero row of zero columnand the bit numerical value in the offset m of the reference bitarrangement is bm.vx=b(4*p+q)  (Formula 1)vy=b(p+3*q)  (Formula 2)

When this is generalized, and when the number of cluster informationcarriers which constitute a virtual block is N, the number of columns ofa virtual block is r, and the integer obtained by rounding up N/r is c,Formula 1 and Formula 2 become as follows, respectively.vx=b(r*p+q)  (Formula 3)vy=b(p+c*q)  (Formula 4)

That is, in digital information carrier formed by coding the bitnumerical value of each axis of p rows and q columns to satisfy formulas3 and 4, it is realized to form the virtual block which consists of crows and r columns in arbitrary places.

When the coordinate axis in the above contents is also generalized andis expressed in another way, it becomes as follows.

When the i-axis positive direction is used as the main scanningdirection and the j-axis positive direction as the sub-scanningdirection, two bit numerical values v (i, j) and v (i+1, j) adjacent inthe main scanning direction (the i-axis positive direction) satisfy thefollowing formulas 5 and 6.v(i, j)=bm  (Formula 5)v(i+1, j)=bm+1  (Formula 6)

On the other hand, two bit numerical values v (i, j) and v (i, j+1)adjacent in the sub-scanning direction (the j-axis positive direction)satisfy the following formulas 7 and 8, when the arrangement length ofthe main scanning direction of a logical block is a.v(, j)=bm  (Formula 7)v(i, j+1)=bm+a  (Formula 8)

In order to apply to the bit numerical value vx of the X-axis direction,since the main scanning direction for bit arrangement formation is theX-axis positive direction and the sub-scanning direction is the Y-axisnegative direction, the i-axis positive direction is set as the X-axispositive direction and the j-axis positive direction as the Y-axisnegative direction. In addition, in order to apply to the bit numericalvalue vy of the Y-axis direction, the i-axis positive direction is setas the Y-axis negative direction and the j-axis positive direction asthe X-axis positive direction.

The concept of the virtual block concerned may be extended and thecontent of the virtual block for showing unit positional information andthe form of the virtual block may be separated. This is explained usingFIG. 26.

FIG. 26 is the figure showing an example of virtual blocks with flexibleforms.

If the concise definition of a virtual block is “a group which can formthe predetermined bit arrangement having the arrangement length of 12 byat least one of the bit numerical value of the X-axis direction and thebit numerical value of the Y-axis direction,” the four regions whichconsist of 12 elements surrounded by the bold lines in FIG. 26, that is,26-1 to 26-4, are all virtual blocks.

If the groups 26-1 and 26-2 surrounded by the bold solid line in FIG.26( a) are unified using the upper left end as the starting point, theX-axis positive direction as the main scanning direction and the Y-axisnegative direction as the sub-scanning direction, the bit arrangementsobtained become X16 to X27 and X2 to X13, respectively, and the offsetvalues become consecutive. For this reason, all serve as the partialarrangements of the reference bit arrangement and become virtual blocks.

In addition, if the bit numerical values of the Y-axis direction areunified for the groups 26-3 and 26-4 surrounded by the bold solid linesin FIG. 26( b) and a bit arrangement is formed, they become Y0 to Y11and Y13 to Y24, respectively. Since each of these serve as the partialarrangement of the reference bit arrangement, the groups 26-3 and 26-4become virtual block.

Here, it should be noted that the virtual block for recognizing the bitarrangement of the X-axis direction and the virtual block forrecognizing the bit arrangement of the Y-axis direction may be definedindependently. For this reason, it is permitted that the bit numericalvalue about the X-axis direction and the bit numerical value about theY-axis direction can be decoded from different cluster informationcarriers in a group of recognized digital information carriers.

Thus, when the bit arrangement of one direction of the coordinate axisis obtained from a virtual block, in order to generate positionalinformation using other reference bit arrangement having a longerarrangement length, this bit arrangement may be used. That is, thepositional information may be generated using a plurality of bitarrangements for reference.

In addition, it should also be noted that the form of a virtual blockdoes not have to be a square of three rows and four columns in as thiscase. This is because the only requirement of a virtual block is tocontain a predetermined number of cluster information carriers formed bycoding consecutive bit numbers, and the form of the whole block isarbitrary.

The explanation of a virtual block is further continued using FIGS. 27and 28.

FIG. 27 is the figure wherein a virtual block and the recognition rangeare displayed on an example of the bit matrix formed by decoding digitalinformation carrier.

FIG. 28 is the figure wherein virtual block and the matrix element whichcan be mutually replaced with the recognition range are displayed on anexample of the bit matrix formed by decoding digital informationcarrier.

One of the virtual block regions is shown in FIG. 27 by the bold line.In addition, the circle by the solid line is an example of therecognition range which includes the virtual block. Moreover, therecognition range is a range recognized by a series of image recognitionprocessing, and only the cluster information carriers contained in therecognition range can serve as constituent elements of a virtual blockin a series of processing. The recognition range shifts by movement ofthe input device, and the number of cluster information carriers in therecognition range also shifts in connection with this. For example, thecluster information carrier contained in the recognition range of thesolid line of FIG. 27( a) has the shape of a rectangle of three rows andfive columns, and the one in the recognition range of the solid line ofFIG. 27( b) has the shape of a rectangle of four rows and four columns.

Here, when the recognition range moves a little horizontally in FIG. 27(a) and assumes the position of the dashed line circle, for example, itbecomes difficult to recognize the cluster information carrier of X5Y4and the cluster information carrier of X13Y6 which could be recognizedin the recognition range denoted by the solid line circle. In addition,when it moves to the position of the dotted line circle, it becomesdifficult to recognize all the cluster information carriers (X5Y4, X9Y5,and X13Y6) of the column on the left end of the virtual block shown bythe bold line. For this reason, it becomes difficult to recognize avirtual block having X5Y4 as the starting point, and it also becomesseemingly difficult to acquire the information which is obtained bydecoding this virtual block and is related to position recognition.

However, even in this case, by removing the above-mentioned left endcolumn in the virtual block shown by the bold line from the virtualblock, and by, instead adding X9Y16, X13Y17, and X17Y18 as the right endcolumn, a new virtual block which uses X6Y7 as a starting point as shownby the dashed line is constructed. For this reason, the one which usesX6 to X17 as elements for the bit arrangement of the X-axis directionand Y7 to Y18 as elements for the bit arrangement of the Y-axisdirection is formed by decoding this virtual block, and the informationconcerning position recognition is acquired based on this. In addition,even if the positional information in this case differs from thepositional information acquired from the virtual block formed by usingX5Y4 as the starting point which has been recognized in the solid linecircle, since the difference is correlated to the movement of therecognition range, this is not problematic.

In addition, the same can be said for the movement of the virtual blockaccompanying vertical movement, as outlined in FIG. 27( b).

When the recognition range moves to both the X-axis and the Y-axis, asit is shown in FIG. 28, a virtual block moves. When it moves from therecognition range shown with the solid line circle in the direction ofthe lower right and moves to the recognition range shown with the dashedline circle, it becomes difficult to recognize the cluster informationcarrier of X6Y7 of the upper left end among the virtual blocks expressedwith the bold line. When this cluster information carrier cannot berecognized, the remaining virtual block will include 11 bit numericalvalues (X7-X17) of the X-axis direction and 11 bit numerical values(Y8-Y18) of the Y-axis direction.

In order to complete the virtual block concerning the X-axis directionhere, it is good to complement the cluster information carrier whichshows X6 or X18. Thus, in this invention, as shown in FIG. 28( a), it ispossible to complement by X18Y21 to reconstruct a virtual block.Similarly, in order to complete the virtual block of the Y-axisdirection, X21Y19 is used as shown in FIG. 28( a).

It should be noted that the form of the virtual block is no longer asquare of three rows and four columns in these cases. Since the blockform is arbitrary for a virtual block, it becomes possible to select asuitable form according to cluster information carrier contained in therecognition range. For this reason, the range needed as a recognitionrange becomes narrower compared with the case where logical block byprior art in which the block form is fixed is employed, and it isrealized to set the number of cluster information carriers contained inthe recognition range fewer. Therefore, image processing required forposition recognition can be managed in a short time.

It may be possible to also decode 12 or more bit arrangements dependingon the place of the recognition range. For example, in the recognitionrange after movement shown with the dashed line circle, X19Y13, X20Y16,and X21Y19 can be decoded as the X-axis direction, and X14Y20 and X18Y21can be decoded as the Y-axis direction.

In addition, it may become difficult to recognize cluster informationcarriers other than those constituting the starting point among thecluster information carriers which serve the angle parts of a virtualblock depending on move direction of the recognition range. In formingthe bit arrangement of the X-axis direction, correspondence whenrecognizing becomes difficult this way is shown in FIG. 28( a). In thevirtual block shown by the bold line, when it becomes impossible torecognize X9Y16 of the upper right end, a virtual block may be build byusing X9Y5 of the direction of the lower left instead of X9Y16. In thenewly built virtual block, the consecutive bit arrangements from X6 toX17 are formed by the unifying method until now which uses the X-axispositive direction as the main scanning direction and the Y-axisnegative direction as the sub-scanning direction with the upper left endas the starting point. Similarly, the consecutive bit arrangements fromX6 to X17 are formed by using X5Y4 of the direction of the upper left inthe case where recognition of X17Y18 of the lower right end isdifficult, and by using X14Y20 of the direction of the upper right whenin the case of X14Y9.

The absolute same is said for the bit arrangement of the Y-axisdirection, and the correspondence relationship of the replacement in thevirtual block shown by the bold solid line is shown in FIG. 28( b).

A virtual block reconstructed by the move direction of the recognitionrange has a part of cluster information carrier serving as theconstituent element of the virtual block before movement is replacedthis way. For this reason, regardless of the direction of the movement,many constituent elements of the virtual block reconstructed have theconstituent elements of the virtual block before movement as overlappingportion. Therefore, in image processing of a new virtual block, many ofthe data of the virtual block before movement are used, and the loss ofthe processing based on having reconstructed the virtual block issuppressed to the minimum. On the other hand, in the logical block ofthe shape of a tile by prior art, the new logical block constituted bymovement cannot use the data of the logical block before movement atall.

In addition, when the recognition range moves diagonally and it becomesimpossible to recognize three cluster information carriers whichconstitute an end of a virtual block, the cluster information carrierswhich became difficult to recognize are not replaced individually, but anew virtual block is built by moving the virtual block as a whole as itis in the shape of a square to the diagonal direction correlating to themovement of the recognition range.

The parameter for which a scan type or a block recognition type imageinput device is asked is determined by the circular recognition rangeused in the above-mentioned explanation. For example, in the case of theimage input range of a typical rectangle, it is required first tocontain the above-mentioned recognition circular. Next, the number ofpixels assigned for every cluster information carrier is calculated fromthe physical resolution of the image input device. This is because thelevel of recognition errors and the image-processing speed in the imagerecognition depend on the number of assigned pixels. Specifically, whenthere is a large number of assigned pixels, since the number of pixelswhich constitute an image object increases incorrect recognition is notlikely to occur but calculation load also increases. On the other hand,although calculation load decreases when a small number of pixels areassigned, since the difference in the number of pixels between an imageobject and a ghost dot decreases, the rate of occurrence of recognitionerrors rises.

Although explanation was given above by assuming 12 as the number ofcluster information carriers which constitute a virtual block, thenumber is essentially arbitrary. Even if a virtual block is constitutedfrom ten cluster information carriers, there is no change at all in thearrangement of cluster information carrier. Only the arrangement lengthof the bit arrangement obtained from the virtual block becomes 10. Inaddition, by this change, the number of bits which can be used in orderto acquire positional information decreases, and the number ofcoordinates which a digital information carrier can display becomes210-1 from 212-1.

Or, even if the arrangement length of the bit arrangement used in orderto acquire positional information is 10, 12 cluster information carrierarrangements may be read to generate a bit arrangement having thearrangement length of 12 as explained so far. In this case, since it isok as long as there are partial arrangement of length 10 in order toacquire positional information, the two remaining bit numerical valuesare used as redundant data. It should be noted that this redundant datacan fully be utilized. It is because the arrangement length of the bitarrangement required for decoding and the arrangement length of therecognized cluster information carrier arrangement are completelyindependent. For this reason, it is possible to increase the number ofredundant data further and to improve a display method or an inputmethod which causes incorrect recognition, and to elongate thearrangement length of cluster information carrier arrangement. Inaddition, the bit numerical values from the cluster information carrierthat are used as redundant data are arbitrary. When using the virtualblock 25-1 of FIG. 25 as an example, the first two bit numerical values(X0 and X1) about the X-axis direction may be redundant information, orit may be the last two (X10 and X11). Or, it may be the first and thelast (X0 and X11). Furthermore, cluster information carriers correlatingto the bit numerical values used as redundant data may differ in theX-axis direction and the Y-axis direction.

The redundant data contained in a virtual block can be used for judgingthe existence of incorrect recognition, or it can be used for correctingwhen there is incorrect recognition. When the display distortion valueof each cluster information carrier is acquired, redundant data can alsobe set so that the one having the highest reliability level in thecluster information carrier with redundant data is included in thecluster information carrier arrangement to actually acquire positionalinformation. In addition, correcting recognition errors is realized alsoby combining the data obtained from the recognized cluster informationcarrier in the recognition range and in the range outside of a virtualblock with redundant data. For example, if there is one which shows thesame bit numerical value as any of the cluster information carriers thatconstitute a virtual block and are in a cluster information carrier inthe range outside of a virtual block, the cluster information carrierwith highest reliability may be used for identifying positionalinformation by measuring the amount of distortion of each clusterinformation carrier.

This is explained using FIG. 27( a). X9Y5 and X9Y16 are contained in therecognition range shown with the solid line, and X9 is contained in thecluster information carriers as the bit numerical value of the X-axisdirection. In this case, as a result of decoding of the two clusterinformation carriers, when two different numerical values are obtained,although they both should be a numerical value which means X9, it isnecessary to judge which value is closer to the truth. At this time, itis good to consider true the decoded bit numerical value thatcorresponds to the smaller distortion value of both cluster informationcarriers. In addition, cluster information carrier which was not usedfor decoding may be presumed to have low reliability and this clusterinformation carrier should not be used for decoding the bit of theY-axis direction. In a specific explanation, when X9Y16 has a higherdistortion value, the bit of the X-axis direction is decoded using X9Y5,and for decoding the bit of the Y-axis direction, X20Y16 which has thesame bit numerical value of the Y-axis direction in the recognitionrange is used instead of using X9Y16.

In addition, in order to regulate the direction of the bit arrangementdecoded and recognized, such redundant data may be used. This point isexplained using FIG. 29.

FIG. 29 is showing an example of a digital information carrier whichuses cluster information carrier with high symmetry and which does nothave directional dependency in the cluster information carrier interval.

Even if a virtual block is decoded and a bit arrangement is obtained, inthe case of a digital information carrier as shown in FIG. 29, it isimpossible to perform attribution of the X-axis direction and the Y-axisdirection. In order to solve such ambiguity, the cluster informationcarrier arrangement is first obtained by the predetermined method andthe virtual block of the unknown direction is recognized. Next, the bitarrangement of a predetermined length, required in order to obtainpositional information from the bit arrangement formed by decoding thearrangement is extracted, and positional information is acquired. Theprocedure is as shown in FIG. 5, and the offset value in the case wherethe bit arrangement constitutes the partial arrangement of the referencebit arrangement is obtained as the information showing the position.Then, it is confirmed whether the bit arrangement which consists of thewhole cluster information carrier arrangements also containing redundantdata other than the bit arrangement used in order to acquire positionalinformation constitutes the partial arrangement in the reference bitarrangement. In the case where it does not constitute a partialarrangement, the recognition direction of the virtual block may beunsuitable so the obtained bit arrangement is the reverse of theoriginal bit arrangement meaning that the reversed bit arrangementmatched the partial arrangement of the bit reference arrangement bychance. Thus, in such a case, the bit arrangement obtained from thevirtual block is reversed, and the same confirmation work is performed.That is, by performing comparison with the reference bit arrangementusing a bit arrangement longer than the necessary minimum arrangementlength in order to acquire positional information, deriving wrong offsetvalues from the reversed bit arrangement obtained due to the unsuitablerecognition direction and thus false position recognition can beavoided.

In addition, when the bit arrangement containing redundant data alsoconstitutes the partial arrangement, the bit arrangement is obtainedfrom a virtual block similarly in the direction of an axis whichintersects perpendicularly this time, and positional information isacquired while confirming the direction. Since attribution of the axisis not performed for the information about the set of coordinatesacquired this way, it is unknown which the X-axis is. However, since thepositive direction of each coordinate axis has been determined by theabove-mentioned technique, from this information the X-axis can beunambiguously identified. This is because the axis on the right-handside of each configuration vector is the X-axis and the axis on theleft-hand side is the Y-axis for the same starting point and both axesshown in a vector shape. This way, the coordinates of each axis arecorrectly understood.

However, the coordinates acquired this way are preliminary coordinateswhich are not the final coordinates showing the position of therecognition range, and it is needed to perform conversion according tothe coordinate system of the document. This point is explained usingFIG. 30. that shows another example of the virtual block concerning theinvention of this application.

As shown in FIG. 30, the bit arrangements of the X-axis direction arecompletely identical for the virtual block 30-1 shown by the dotted lineand the virtual block 30-2 shown by the solid line. And thus, these giveidentical X coordinate values. From this, the line segment whichconnects the cluster information carrier of the upper left end of eachvirtual block is recognized to be parallel to the Y-axis. The linesegment which connects the cluster information carrier of the upper leftend of each of the virtual block 30-2 shown by the solid line and thevirtual block 30-3 shown by the dashed line is similarly recognized tobe parallel to the X-axis. Therefore, it can be said that the two linesegments shown in FIG. 30 visualize the initial stage coordinate systemobtained by the arrangement of cluster information carriers which hasbeen explained as an example here.

The relationship of the coordinates (X, Y) acquired by decoding andcorrelating matrix arrangement (R, C), that is, the coordinates on adocument, is calculated as follows based on Formulas 1 and 2.R=(3*X−Y)/11  (Formula 9)C=(4*Y−X)/11  (Formula 10)

By applying the formula concerned, the arrangement position of thecenter of gravity of the cluster information carrier of the upper leftend of the decoded virtual block is identified. Once the position of thecenter of gravity is identified, the center of the recognition range,the direction, and other parameters are easily found by using theexisting technology.

It has been explained so far by using cluster information carriersarranged in three rows and four columns as a virtual block. But, it isnot restricted to this arrangement. A virtual block may have any numberof arrangements and any arrangement form. However, the coefficient ofFormulas 9 and 10 also change according to the size of a virtual block.When the size of a virtual block is c rows and r columns, specifically,it is as follows.R=(c*X−Y)/(c*r−1)(Formula 11)C=(r*Y−X)/(c*r−1)(Formula 12)

In addition, although explanation has been given using clusterinformation carriers as the constituent elements of a virtual block,some or all of the constituent elements may be image objects.

Furthermore, arrangement of cluster information carriers is performedindependently of the virtual block arrangement, and it may be made sothat the arrangement relationship carry information independently of thevirtual block. An example is shown in FIG. 31.

FIG. 31 shows the case wherein cluster information carriers surroundedby a rectangle or a circle are arranged out of alignment, a little moredownward than the other cluster information carriers for the digitalinformation carrier shown in FIG. 29.

Every fourth cluster information carriers is displaced downward out ofalignment for all rows as can be clearly seen in FIG. 31. However, inorder to avoid appearance of specific patterns on the display medium,etc. and to create a more uniform distribution, the columns of clusterinformation carrier that are displaced downward differ between odd rows(surrounded with the circle) and even rows (surrounded with thequadrangle).

According to this arrangement, the direction of the document is obtainedas follows. First, four consecutive cluster information carriers of thedirection of a row or the direction of a column are recognized as abundle.

Next, four sorts of subsets formed by removing one cluster informationcarrier from the four cluster information carriers are made.

Then, straight line approximation is performed with the threeconstituting cluster information carriers of each subset, and the subsetwherein the error value is the minimum in the approximation is selected.

Finally, the center of gravity of one cluster information carrier whichdoes not constitute the selected subset, that is, of the clusterinformation carrier out of alignment downward, is substituted in theapproximation straight line of the subset.

When the result of this substitution is positive, it is judged that theapproximation straight line shows the X-axis direction, and that thedirection from the left to the right is the positive direction.

On the other hand, when the result of the substitution is negative, itis judged that the approximation straight line was recognized in areversed state and the X-axis direction is derived although it isnecessary to perform 180-degree rotation of the image and to reverse thedirection of the axis.

Or, when the result of subtraction is close to 0, it means that the fourcluster information carriers are almost on the straight line, and inthis case, since it is judged that the approximation straight line showsthe Y-axis direction, the cluster information carrier is recognized inthe direction perpendicular to this approximation straight line, thesame processing is performed, and the direction confirmation of theX-axis is performed.

It should be noted that direction recognition is performed completelyindependently of the information which the cluster information carrierhas individually. However, the above-mentioned arrangement is a mereillustration and the unit information carrier which constitutes avirtual block is not restricted to cluster information carrier, but maybe an image object. In addition, other modes of arrangement of clusterinformation carriers may be used. Since the direction recognition basedon the arrangement of cluster information carriers shown here and thedirection recognition using the above-mentioned bit arrangement aremutually independent, these may be used in combination.

As explained above, the digital information carrier concerning thisinvention is constituted by the parameters which are mutuallyindependent or have very loose mutual dependency, such as theconfiguration of cluster information carriers, the maximum number ofbits which a cluster information carrier can display, the bitarrangement length, size of a virtual block, the arrangement interval ofcluster information carriers, the arrangement of cluster informationcarrier, etc. A digital information carrier which has high flexibilityis realized by using such a structure. This is because these elementscan be used independently or in combination according to the situation.

FIRST EMBODIMENT

Next, an example of the system for outputting digital informationcarrier concerning this invention is shown.

FIG. 32 is the conceptual figure of the system for displaying digitalinformation carrier concerning this invention.

The digital information carrier generation system 11 is equipped with aninput device 101 for inputting the information which the digitalinformation carrier outputted or at last should have, the processingdevice 102 for generating digital information carrier which has theinformation inputted into the input device 101 and for performingprocessing that converts the data format so that the output device 103can output the digital information carrier, and the output device 103for outputting the information concerning the digital informationcarrier based on the converted data. In addition, communication ofinformation to at least one direction is enabled by communication means,such as a communication cable and radio, between each device.

The input device 101 may be a keyboard, a mouse, a microphone, etc. forpeople to input information, may be a scanner, a camera, etc. foroptically reading media, such as paper, on which characters and symbolsare displayed, or may be a reading device for reading a magneticrecording medium, an optical recording medium, a semiconductor recordingmedium, etc. wherein information is recorded in the format other thanwhat human can directly recognize.

The processing device 102 comprises the input/output part 102 a forexchanging data with the input device 101 or the output device 103, thememory part 102 c which has a memory region for storing datatemporarily, and the processing part 102 b which handles processing ofdata. The data inputted from the input device 101 is stored in thememory part 102 c through the input/output part 102 a, the processingpart 102 b forms the data concerning the digital information carrierwhile reading the required data from and writing on the memory part 102c suitably, and it is outputted to the output device 103 through theinput/output part 102 a.

The output device 103 may be a printing machine, a printer, etc. fordisplaying the digital information carrier. on a paper-like medium, maybe a liquid-crystal-display element, CRT, etc. for variably displayingthe digital information carrier, or may be a write-in device for writinginformation on storage media, such as a magnetic recording medium, anoptical recording medium, a semiconductor recording medium, etc., in theformat other than what human can directly recognize.

In addition, although FIG. 32 was explained as a digital informationcarrier generation system wherein the input device 101, the processingdevice 102, and the output device 103 are independent of each other,some of them may be unified physically. Moreover, each device may beconnected to networks, such as the Internet.

Next, an example of operation of the digital information carriergeneration system 11 is explained based on FIG. 33 and FIG. 34.

FIG. 33 is the flow chart conceptually showing an example of operationof the digital information carrier generation system 11.

FIG. 34 is the conceptual figure for explaining operation of the digitalinformation carrier generation system 11.

Hereafter, as shown in FIG. 34( a), explanation is given using as anexample the process for virtually dividing the surface of the paper-likemedium 111 into 25 regions of five rows and five columns and generatingthe carrier wherein the digital information carrier which has thecoordinate information of the paper-like medium 111 is displayed on thepaper-like medium 112 using the digital information carrier generationsystem 11.

To simplify, the surface of the paper-like medium 111 is virtuallydivided into 25 regions of five rows and five columns (Step S101). Inthe case currently examined, the simple bit arrangement shown in FIG. 4can be used. As a group of X coordinate value and Y coordinate value,the coordinates of each element (it may also be called a cell or ablock) can be defined as shown in FIG. 34( a) (Step S102). In addition,it should be noted that the logical block including the bit value whichcontinues directly from the coordinate information shown in FIG. 34( a)cannot be formed.

Next, the argument is proceeded using the logical block of two rows andtwo columns as the simplest logical block that can be though of. Themain scan is to the right using the upper left end as the startingpoint, and the direction of the sub-scan is downward (Step S103). Fromthe coordinate information on FIG. 34( a), the target digitalinformation carrier can be generated as follows.

The X coordinate value (data) can be coded as shown in FIG. 34( b). Thefirst 5 bit values, that is, 0, 1, 2, 3, and 4, of the offset valueshown in FIG. 4 is used for the first row. The 2nd row uses the bitvalues from 2 to 6, and the 3rd row uses the bit values from 4 to 8. Itis the same for each of the following rows (Step S104).

It should be noted that only 13 (bit value 0-12) is required as the bitarrangement length in spite of having 25 elements (cells). Since therequired bit arrangement length is 13, a bit arrangement having thearrangement length of 15 as shown in FIG. 4 can be used safely.

Next, an actual bit value is applied to each element. The bitarrangement correlating to the offset value of FIG. 4 is read and thosevalues are made to correlate to each element. For example, since theoffset value of row zero and column zero is 0, the bit arrangement is0001 and each value is applied to row zero and column zero, row zero andcolumn one, row zero and column two, and row zero and column three.Since the offset value of row zero and column one is 1, the bitarrangement is 0011 and each value is applied to row zero and columnone, row zero and column two, row zero and column three, and row zeroand column four. Since the offset value of row zero and column two is 2,the bit arrangement is 0111 and each value is applied to row zero andcolumn two, row zero and column three, and row zero and column four, butit is not necessary to apply the last 1 anywhere. Hereafter, a bit valueis similarly applied to each line and each column. FIG. 34( c) wasobtained this way (Step S105).

Y coordinate value (data) is carried out similarly and FIG. 34( d) isobtained correlating to FIG. 34( b). Subsequently, an actual bit valueis applied to each element of FIG. 34( d), and FIG. 34( e) is obtained.However, in the case of the Y coordinates, unlike the case where thedirection to apply was related to the X coordinates, it is applied inthe Y-axis direction. For example, since the offset value of the rowzero and column zero is 0, the bit arrangement is 0001 and each value isapplied to row zero and column zero, row one and column zero, row twoand column zero, and row three and column zero (although the stepsconcerning the Y coordinates are not specifically shown, they are thesame as Steps S104 and S105 for the X coordinates).

Here, by combining the X coordinate and the Y coordinate values, FIG. 34(f) is obtained. This can be easily obtained by combining FIG. 34( b)and FIG. 34( d). In addition, it should be noted that FIG. 34( f) wasnot obtained by coding directly the coordinate value of each element ofFIG. 34( a). For any block of 2×2 in FIG. 34( f), four consecutive X bitvalues and four consecutive Y bit values are surely included there.

If FIG. 34( f) is expressed with an actual bit value, FIG. 34( g) can beobtained from FIG. 34( c) and FIG. 34( e). Therefore, as the nextoperation, the bit value of this FIG. 34( g) will be expressed on apaper-like medium using cluster information carrier.

Here, the use of a cluster information carrier which has 2-bitinformation is considered. Those shown in FIG. 13, FIG. 14, FIG. 15,FIG. 22, and FIG. 23 can be used as a cluster information carrier whichhas 2-bit information. It is good to adopt the configuration shown inFIG. 11 in the case being examined now using cluster information carriershown in FIG. 10 (Step S106).

Naturally, the bit value expressed by each cluster information carriermust be the same as FIG. 34( g). For example, the cluster informationcarrier at the upper left of FIG. 34( g) are 0, 0, and this means X=0,Y=0. Then, when the cluster information carrier correlating to X=0, Y=0is called for, in FIG. 10, the one on the leftmost-hand side can befound. Therefore, this cluster information carrier is printed to theelement at the upper left of the paper-like medium. Hereafter, thecluster information carrier correlating to the bit value of each elementis determined similarly, and the data for output is formed (Step S107).This data for output is once stored in the memory part 102 c of theprocessing device 102, is outputted to the output device 103 through theinput/output part 102 a, and is printed. FIG. 34( h) shows the typicalappearance of the printout. The paper-like medium 112 will have digitalinformation carrier this way. In addition, the cluster informationcarrier correlating to the bit value of each element may be constitutedso that the cluster information carrier shown in FIG. 10 is stored onthe memory part 102 c of the processing device 102 and it can beautomatically found by the processing part 102 b.

About decoding, it is as follows.

An arbitrary 2×2 block is selected on the paper-like medium on whichdigital information carrier is printed. The cluster information carrierwritten in each block (element) is read, and the bit arrangement isgenerated according to FIG. 10. The bit arrangement can be obtained forthe X and the Y coordinates, respectively. For example, it is 1110 forthe X coordinate, and it is 1101 for the Y coordinate. However, for theX coordinate, it is read in the order of the upper left, the upperright, the lower left, and the lower right, and for the Y coordinate, itis read in the order of the upper left, the lower left, the upper right,and the lower right.

The obtained bit arrangement is compared with the reference bitarrangement of FIG. 4. to find the portion in agreement. For example,for the X coordinate value, since it is 1110, the offset value 4 isacquired from the reference bit arrangement of FIG. 4. This can bedetermined unambiguously. Similarly, for the Y coordinate value, sinceit is 1101, the offset value 5 is acquired. Since the offset values are(4, 5), in the original region divided virtually, it can be found thatit is (2, 1) using FIG. 34( a) and FIG. 34( f). In addition, the methodstated in FIG. 30 can be applied to the conversion to FIG. 34( a)showing the original coordinate value from FIG. 34( f) showing the codedcoordinate value. Positional information can be obtained as mentionedabove. In addition, although a 2-bit information arrangement was used ascluster information carrier, cluster information carriers with 1-bitinformation can also be used naturally.

SECOND EMBODIMENT

Next, an example of a system which enables recognition of theinformation included wherein the digital information carrier concerningthis invention is displayed is shown.

FIG. 35 is the conceptual figure of the system for recognizing theinformation included in the digital information carrier concerning thisinvention.

The digital information carrier generation system 21 is equipped withthe input device 201 for inputting the digital information carrierdisplayed on the predetermined medium, the processing device 102 fordecoding a digital information carrier from an image object inputtedinto the input device 201 and generating the information which thedigital information carrier has, and for performing processing thatconverts the data format so that the output device 203 can output theinformation, and the output device 203 for outputting the informationwhich the digital information carrier has based on the converted data.In addition, communication of information in at least one direction isenabled by communication means, such as a communication cable or radio,between each device.

As the input device 201, an optical image input device, such as ascanner, a CCD camera, a CMOS camera, and a photo-coupler, or otherdisplay input devices can be used. The following explanation is given byusing an image input device as an example.

The processing device 202 comprises the input/output part 202 a forexchanging data with the input device 201 or the output device 203, thememory part 202 c which has a memory region for storing datatemporarily, and the processing part 202 b which handles processing ofdata. The data inputted from the input device 201 is stored in thememory part 202 c through the input/output part 202 a, the processingpart 202 b forms the predetermined data while reading the required datafrom and writing on the memory part 202 c suitably, and it is outputtedto the output device 203 through the input/output part 202 a.

The output device 203 may be a printing machine, a printer, etc. fordisplaying the digital information carrier on a paper-like medium, maybe a liquid-crystal-display element, CRT, etc. for variably displayingthe digital information carrier, or may be a write-in device for writinginformation on storage media, such as a magnetic recording medium, anoptical recording medium, a semiconductor recording medium, etc., in theformat other than what human can directly recognize.

In addition, although FIG. 35 was explained as a digital informationcarrier generation system wherein the input device 201, the processingdevice 202, and the output device 203 are independent of each other,some of them may be unified physically. Moreover, each device may beconnected to networks, such as the Internet.

Next, an example of operation of the digital information carrierdecoding system 21 is explained based on the flow charts shown in FIG.36.

FIG. 36 (1)-(3) are the flow charts conceptually showing an example ofthe first half of operation of the digital information carrier decodingsystem 21.

First, the predetermined storage area of the memory part 202 c withwhich the processing device 202 is equipped is cleared, and workspace issecured (Step S201).

Next, the control signal for performing image reading is outputted onpredetermined image input conditions to the input device 201 (StepS202). The input device 201 into which this control signal was inputtedreads an image, and outputs it to the processing device 202 as imagedata.

After this image data is stored in the predetermined storage area of thememory part 202 c with which the processing device 202 is equipped (StepS203), the recognition processing as an image object is performed (StepS204).

When judgment is performed at Step S205 on whether a plurality of imageobjects have been recognized and when it is judged that a plurality ofimage objects were recognized, a number is assigned to each recognizedimage object so that it can be distinguished from others, these arestored with each positional coordinate in the storage area for poolingimage object data (Step S206).

Here, in order to store positional coordinate, the information about thecoordinate system is needed. When recognition of the information on thiscoordinate system is possible in the stage of Step S204 for recognizingan image object, this is used, and when the information is not acquired,the coordinate system of image data is used as it is.

On the other hand, when it is judged that a plurality of image objectswere not recognized, after adjusting image reading conditions, such asbrightness and contrast (Step S207), it is proceeded to Step S201 andthe control signal of image reading is outputted again.

Here, it may be control wherein image data is continuously outputtedfrom the input device 201, and the processing device 202 reads as neededthrough the input part 202 a. In such control, Step S202 is unnecessary.In addition, when Step S207 is performed, the image reading conditionset by this processing is made so that it is reflected in the next imagereading. Moreover, when Step S207 is performed continuously for apredetermined number of times, for example, 10 times, the operator ofthe system may be notified by an error signal.

Next, the processing for recognizing a cluster information carrier froma plurality of image objects stored in the storage area for poolingimage object data.

First, among a plurality of the image objects stored in the storage areafor pooling image object data, arbitrary image object is read (StepS208).

Next, a judgment is made whether an image object that can be furtherread is stored in the storage area for pooling image object data (FIG.36 (2), Step S209).

When it is judged that there are image objects that can be read at StepS209, those image objects are read from the predetermined storage areaof the memory part 202 c one by one, and it is judged whether clusterinformation carrier is constituted. That is, the cluster function isapplied (Step S210). An example of the judgment processing is as shownin FIG. 2.

Judgment processing is performed on whether the image objects read atSteps S208 and S210 constitute a cluster information carrier with any ofthe other image objects (Step S211).

When it is judged that the image object is a constituent element ofcluster information carrier at Step S211, the image data of the clusterinformation carrier to which the image object belongs is stored with thepositional coordinate to the storage area for pooling the data ofcluster information carrier (Step S212). Then, the image object isdeleted from the storage area for pooling the image object (Step S213).The image object read at Step S213 is deleted at this step forpreventing the same cluster information carrier from being recognizedtwice.

Here, in order to store the positional coordinate of cluster informationcarrier, the information about the coordinate system is needed. Thisinformation is used when such recognition is possible in the stage ofStep S210 where the cluster function is applied, and the coordinatesystem of image data is used as it is when it is not obtained. Forexample, when the information on coordinates is included in thearrangement of cluster information carriers as shown in FIG. 24 or FIG.31, the information on the coordinate system is acquired by obtainingthe center-of-gravity coordinates etc. of the plurality of clusterinformation carriers.

On the other hand, when it is judged that the image object is not theconstituent element of cluster information carrier at Step S211, theimage object is deleted from the storage area for pooling image objectdata (Step S213).

When the image object concerning the processing is a ghost dot, apossibility of being judged to constitute cluster information carrier atStep S211 is low. For this reason, that image object has a highpossibility of being eliminated at Step S213 without becoming theconstituent element of cluster information carrier.

When the predetermined image object is deleted at Step S213, anotherimage object is read from the predetermined storage area of the memorypart 202 c (Step S214), and it proceeds to Step S209 to apply thecluster function again.

On the other hand, when it is judged that there is no image data to beread at Step S209, the image object read at Step S208 or S214 is thelast image object stored in the storage area for pooling image objectdata, and since there is only one image object, judgment processing ofwhether to constitute cluster information carriers cannot be performed.

Thus, it is judged that execution of Step 210 which applies the clusterfunction is unnecessary, and the display distortion value is evaluatedfor all cluster information carriers stored in the storage area forpooling the data of cluster information carrier (FIG. 36 (3), StepS215).

Here, as for the evaluation of the display distortion value, it isdesirable to use not only the form of the image objects which constitutecluster information carrier but also the relative arrangement of those.It is because a cluster information carrier consists of a plurality ofimage objects and it has a display area larger than the image objectitself which constitutes cluster information carrier, and thus, displaydistortion is easily measured. In addition, when the relativearrangement of the image objects is included in the judgment conditions(cluster function) for judging whether to constitute cluster informationcarrier, the relative arrangement concerning the judgment conditionsfulfills predetermined conditions. Thus, it can be used as an evaluationresult of display distortion by quantifying the sufficiency of theconditions.

In addition, although only display distortion was explained as theobject of evaluation here, it is also good to have color difference etc.as the object of evaluation.

As a result of evaluation of the display distortion value in Step S215,cluster information carriers judged that the display distortion value islarge and the degree of display distortion is high have a highpossibility of generating a numerical bit value that differs from thetrue numerical bit value in decoding. Thus, such cluster informationcarriers are deleted from the storage area for pooling the data ofcluster information carrier (Step S216), and are not taken as objects ofdecoding.

Then, judgment processing is performed on whether the number of clusterinformation carriers stored in the storage area for pooling the data ofcluster information carrier has reached the number needed for subsequentprocessing (Step S217).

When it is judged that the data of cluster information carrier of apredetermined number is stored, it proceeds to Step S231 of theprocessing shown in FIG. 37 (1) described later.

On the other hand, since the subsequent processing cannot be performedwhen it is judged that the numbers of data is insufficient, afteradjusting image input conditions (Step S218), it proceeds to Step S201.S218 as well as Step S207 may be made so that they support thecontinuation image input system or they emit an error signal when anunsuitable image is input repeatedly.

Next, explanation on an example of operation of the digital informationcarrier decoding system 21 is continued according to FIG. 37.

FIG. 37 is the flow chart conceptually showing an example in the secondhalf of operation of the digital information carrier decoding system 21.

When cluster information carrier of a predetermined number is judged tobe stored in a predetermined storage area by the judgment processingshown in Step S217 of FIG. 36 (3), those cluster information carriersare read (Step S231), and each cluster information carrier is decoded(Step S232).

An example of the decoding in Step S232 is shown below. First, thecorrespondence relationship data concerning the correspondencerelationship of the relative relationship of a plurality of imageobjects which are the constituent elements of cluster informationcarrier and bit data is beforehand stored in the memory part 202 c. AtStep S232, the data of one cluster information carrier is read from thestorage area for pooling the data of cluster information carrier in thememory part 202 c, it is judged which bit data the cluster informationcarrier correlated to by referring to the correspondence relationshipdata stored in the memory part 202 c, and the bit data obtained as aresult of the judgment is considered as the result of decoding. Thisprocessing is performed for all cluster information carriers stored inthe storage area for pooling the data of cluster information carrier inthis processing.

Here, when the information on the coordinate system as digitalinformation carrier is acquired as a result of decoding, the coordinatesystem is suitably adjusted using the information, and it is decodedagain if needed. On the other hand, when the information on thecoordinate system is not acquired, the coordinate system of image datais used as it is. As an example from which the information on thecoordinate system is acquired in the process of decoding, clusterinformation carrier as shown in FIG. 1 is mentioned. The informationabout the X-axis is acquired from the longest principal diameter of theline segment, and the information about the positive X-axis direction isacquired from the relationship of the relative position of the linesegment and the dot. When the X-axis direction becomes clear, the Y-axisand its positive direction become clear, too. This way, the informationabout the coordinate system is acquired.

Next, the bit matrix which consists of the bit numerical values acquiredby decoding of each cluster information carrier is formed (Step S233).Arrangement of the matrix elements in this bit matrix is based on thepositional coordinate of each cluster information carrier. Specifically,one bit numerical value is arranged in the position of the center ofgravity of the correlating cluster information carrier or in the centralposition defined for every type of cluster information carrier.

About the coordinate system in arrangement of the bit matrix, when thecoordinate system as digital information carrier is clear by theprocessing so far, this coordinate system is used, and when it is notclear, the coordinate system of image data is used.

Here, when the bit numerical value which correlates to some elements ofthe matrix is not acquired due to problems in image recognition etc.,information on this is given to the elements and the matrix is built.This is an expedient processing in construction of subsequent logicalblock.

An example of the bit matrix obtained by such processing is shown inFIGS. 38( a) and 39(a). In addition, in FIG. 39( a), the matrix elementsof which the bit numerical value is not acquired by decoding are shownby “x” which is an error value.

Next, a logical block is selected from a bit matrix (Step S234).Selection of a logical block is performed as follows. First, a matrixelement having a high possibility of being most suitable as the startingpoint of a logical block is selected from the matrix element of theobtained bit matrix. For example, a logical block consists of three rowsand four columns, and when the matrix element of the upper left end isthe starting point, the matrix element of the upper left end of theobtained bit matrix is selected as the starting point of a logicalblock. Next, the partial matrix of three rows and four columns isselected using this matrix element as the starting point, and this isconsidered as a logical block.

The examples wherein the logical block is selected from the bit matrixshown in FIGS. 38( a) and 39(a) according to the above-mentionedselection rule are shown in FIG. 38( b) and FIG. 39( b), respectively.

Judgment is performed on whether each constituent element of the logicalblock selected this way is a bit numerical value, and whether it ispossible to form the bit arrangement by unifying these bit numericalvalues (Step S235).

When it is judged that it is possible to form the bit arrangement, thebit arrangement is formed from the bit numerical values included in thislogical block (Step S236).

This formation of bit arrangement from the logical block is performedbased on the formation rule defined beforehand. For example, when therule is “appointing the horizontal direction facing the right as themain scanning direction and the horizontal direction facing down as thesub-scanning direction for the bit matrix shown in FIG. 38( a), andunifying the logical block”, the bit arrangement obtained according tothis becomes as it is shown in FIG. 38( c).

Then, judgment is performed on whether the obtained bit arrangementforms the partial arrangement that uses any one element of the referencebit arrangement as the starting point (Step S237). An offset value iscalculated when it is judged to form the partial arrangement of thereference bit arrangement (FIG. 37 (2), Step S238). For example, offsetis m when the bit arrangement correlates to the partial arrangementwhich uses the m-th element of the reference bit arrangement as thestarting point.

When the offset obtained this way shows the display position of clusterinformation carrier which serves as a starting point of the logicalblock in a paper-like medium, positional coordinate can be calculatedfrom the offset value (Step S239). After converting the calculationresult into the data format which the output device 203 can process(Step S240), by outputting to the output device 203 (Step S241),predetermined information is extracted from digital information carrierdisplayed on the paper-like medium, and the result is outputted to theoutput device 203.

The bit arrangement obtained from FIG. 38( b) is “011110111001”, andthis is in agreement with “011110111001” from the 11th of the referencebit arrangement “000000000001111011100111111 . . . ” Therefore, thevalue in the decimal system is 1977 and an offset value becomes “10.”The positional information on a paper-like medium is calculated from thenumerical value, and it is shown in FIG. 38( d) using as an example thestate where “10” is displayed on the predetermined position on a liquidcrystal screen 203 a to correlated to a paper-like medium.

In addition, the obtained offset may mean other information, or it mayshow information without the bit arrangement obtained needing thereference bit arrangement.

Next, processing when the logical block selected at Step S234 cannotform bit arrangement is explained. The case where some elements of alogical block column do not show the bit numerical values is mentionedas the case where the bit arrangement cannot be formed, for example, asshown in FIG. 39( b).

In such a case, examination is performed on whether a virtual block canbe built by replacing the matrix element which does not show the bitnumerical value in a logical block with the element of the bit matrix ofthose, other than the constituent element of the logical block (FIG. 37(3), Step S243).

An example of replacing a matrix element and building a virtual block isexplained in the case where bit arrangement is formed according to themain scanning direction and the sub-scanning direction which wereappointed beforehand from the predetermined starting point as mentionedabove based on FIG. 39( b). The bit numerical value of the upper leftend of FIG. 39( b) is regarded as the matrix element of row zero andcolumn zero, and the bit numerical value of the lower right end as thematrix element of row three and column four as related in theexplanation.

Since each element is arranged so that the matrix element of row one andcolumn zero wherein the bit numerical value is not defined in FIG. 39(b) can be replaced with an element outside the logical block adjacent onthe right to the matrix element of row zero and column three (namely,the matrix element of row zero and column four), a new logical block canbe built as shown in FIG. 39( c). This is because 5th element in the bitarrangement, obtained by applying the bit arrangement formation ruleshown previously, to the new logical block becomes a bit numerical valuewhich forms the matrix element of row zero and column four and it is thesame as the bit numerical value which forms the matrix element of rowone and column zero, and as a result, the bit arrangement obtained fromthe logical block after replacement is the same as the bit arrangementbefore replacement. Since the aggregate of the bit numerical value builtthis way conceptually differs from the logical block of the conventionalmatrix arrangement, it is called a virtual block.

In the judgment (Step S244) of whether it is possible to build a virtualblock, when the judgment is possible, it proceeds to Step S236, bitarrangement is formed by this built virtual block, and the subsequentprocessing is also performed. In addition, although it is shown as “thelogical block” in Step S236, even if it is the case of a virtual block,the virtual block is built so that the same rule as the bit arrangementformation rule applied to a logical block can be applied.

On the other hand, when it is judged that construction of a virtualblock is impossible at Step S244, examination is performed on there-selection with different starting point of the logical block, andwhether the virtual block can be built from the re-selected logicalblock (Step S245).

Here, an example where re-selection of a logical block is performed inthe above-mentioned bit arrangement formation method is explained.Suppose the case where the matrix element of row zero and column fourdoes not have a bit numerical value, as in FIG. 39( a). In this case,the virtual block which uses as the starting point the matrix element ofthe row zero and column zero as shown in FIG. 39( c) cannot be formed,either. Thus, it is examined whether the starting point of a logicalblock can be moved one by one from row zero and column zero to form alogical block of three rows and four columns. First, since the matrixelement of row zero and column four does not have a bit numerical valuelike the above, the matrix element of a row zero and column one cannotbe used as the starting point to build a logical block. Since the matrixelement of the row one and column zero does not have the a numericalvalue itself, a logical block cannot be built either by using this asthe starting point. However, the matrix element of the row one andcolumn one can be used as the starting point to build a logical block.Therefore, a bit arrangement is formed based on the logical block usingthe matrix element of the row one and column one as the starting point.In the example shown in FIG. 39 (d), “011100111111” is obtained as bitarrangement and it is in agreement with “011100111111” from the 16th ofthe reference bit arrangement “000000000001111011100111111 . . . ”Therefore, the value by in decimal system is 1855 and the offset valuebecomes “15.”

This way, in the judgment (Step S246) of whether it is possible toperform selection of a logical block or construction of a virtual block,when it is judged that selection or construction is possible, itproceeds to Step S236, a bit arrangement is formed with the applicationof the bit arrangement formation rule to this selected logical block orbuilt virtual block, and subsequent processing is also performed.

On the other hand, when it is judged in Step S246 that selection of alogical block etc. is impossible even after the above processing, it isjudged whether rotation processing of cluster information carrier ispossible (Step S247).

The case where rotation processing of cluster information carrier isimpossible is a case where at least one rotation processing was alreadyperformed and there is no room to perform rotation processing further.

When it is judged that rotation processing of cluster informationcarrier is possible at Step S247, rotation processing of clusterinformation carrier is performed (Step S248). The rotation angle may be90 degrees or 180 degrees. Then, it proceeds to Step S232 and a bitvalue is again decoded for the cluster information carrier afterrotation processing.

On the other hand, when it is judged that rotation processing of clusterinformation carrier is impossible in Step S247, image reading conditionsare adjusted (Step S249), and it proceeds to Step S201 of FIG. 36 (1).In addition, Step S249 as well as Step S207 may support a continuousimage input system, or may emit an error signal when an unsuitable imageis input continuously for at least two times.

In addition, judgment processing of the rotation processing possibilityfor the bit matrix formed by decoding cluster information carrier may beadded between Step S246 and Step S247. When it is judged that it ispossible to perform rotation processing, it may be made so thatpredetermined rotation processing is performed to the bit matrix, and itproceeds to Step S234 to perform processing after logical blockselection to the bit matrix which is obtained by rotating.

In addition, judgment processing of the rotation processing possibilityfor a read-in image may be added between Step S247 and Step S249. Whenit is judged to be possible to perform rotation processing, it may bemade so that predetermined rotation processing is performed to theread-in image, and it proceeds to Step S204 to perform processingrecognition of an image object to the read-in image which is obtained byrotating.

INDUSTRIAL APPLICABILITY

When the information which can identify the position of a constituentelement is coded in the digital information carrier concerned, theinformation regarding the position of the recognition range can beacquired by recognizing a part of the digital information carrierdisplayed. For this reason, identification of the position of a displayrecognition device on a display medium is performed without difficulty.If a display recognition device is attached to a pen and paper is usedas a display medium, tracking of the position of the pen which writesletters on paper and display on a computer can also be realized, forexample.

In addition, the digital information carrier does not stand out whendisplayed and can be easily blended with the existing visualinformation, for example, a character or a photograph, due to thediversity of the display modes. For this reason, when a displayrecognition device is put closer to a photograph on a printed document,a computer can tie up appropriately the printed document and theinformation outside the document relevant to this document, such as anexplanation of that photograph.

1. A physical surface bearing graphical objects recognizable by digitalinformation capturing means, said graphical objects being patterned soas to predetermine groupings thereof that interrelate by a clusteringdefinition establishing clusters of said graphical objects and thatthereby encode primary information at least identifying the placement ofthe clusters of said graphical objects within the entire pattern of saidgraphical objects on said surface, and to predetermine an arrangement ofsaid graphical-object clusters relative to each other that encodessecondary information different from the primary information, saidarrangement of said graphical-object clusters being assigned informationrelating either to coordinate axes for, or to the orientation of, anarray of said graphical-object clusters, wherein: among a number d(wherein d≧4) of said graphical-object clusters arranged consecutively,a number e of graphical-object clusters satisfying the condition e<d/2are arranged offset in a direction orthogonal to an arraying directionformed by the remaining number d−e of graphical-object clusters; and theinformation relating to the coordinate axes is assigned to the arrayingdirection, and the information relating to orientation is assigned tothe offset.
 2. A physical surface bearing graphical objects recognizableby digital information capturing means, said graphical objects beingpatterned so as to predetermine groupings thereof that interrelate by aclustering definition establishing clusters of said graphical objectsand that thereby encode primary information at least identifying theplacement of the clusters of said graphical objects within the entirepattern of said graphical objects on said surface, and to enable, viadigital information capturing means configuration of a logical blockformed by unifying a plurality of unit graphical-object clusters beingthe minimum units for decoding bit data from any said graphical-objectclusters; assigning an item of information to an array formed byunifying any number of constituent elements of a given configuredlogical block, said given logical block being constituted from a largernumber of said unit graphical-object clusters than the number ofelements in the array to which said item of information is assigned; andconfiguration of a new logical block by replacing at least one of theconstituent elements of said given logical block with a unitgraphical-object cluster neighboring said given logical block.
 3. Aphysical surface bearing graphical objects recognizable by digitalinformation capturing means, said graphical objects being patterned soas to predetermine groupings thereof that interrelate by a clusteringdefinition establishing clusters of said graphical objects and thatthereby encode primary information at least identifying the placement ofthe clusters of said graphical objects within the entire pattern of saidgraphical objects on said surface, and to enable, via digitalinformation capturing means configuration of a logical block formed byunifying a plurality of unit graphical-object clusters being the minimumunits for decoding bit data from any said graphical-object clusters;assigning an item of information to an array formed by unifying anynumber of constituent elements of a given configured logical block, saiditem of information being information with which the layout coordinatesof any constituent element of said logical block are specifiable; andconfiguration of a new logical block by replacing at least one of theconstituent elements of said given logical block with a unitgraphical-object cluster neighboring said given logical block.
 4. Aphysical surface bearing graphical objects recognizable by digitalinformation capturing means, said graphical objects being patterned: soas to predetermine groupings thereof that interrelate by a clusteringdefinition establishing clusters of said graphical objects and thatthereby encode primary information at least identifying the placement ofthe clusters of said graphical objects within the entire pattern of saidgraphical objects on said surface; so as to contain a bit matrix Vformed by arranging, in matrix form, array elements b_(m)(m=0 to n−1) ofa reference-bit array B having a predetermined array length n, whereinbit data is correlated to the bit matrix V; so that two matrix elementsv(i,j) and v(i+1,j) neighboring one (i-axis) of the two array axes ofthe bit matrix V satisfy v(i,j)=b_(m) v(i+1,j)=b_(m); and so that twomatrix elements v(i,j) and v(i,j+1) neighboring the other array axis(j-axis) of the bit matrix V satisfy, letting the amount by which thearray elements b_(m) are offset toward the j-axis be a, v(i,j)=b_(m)v(i,j+1)=b_(m+a), wherein the amount of offset a toward the j-axis is aninteger equal to or greater than
 2. 5. A method of decoding, via digitalinformation capturing means, bit data from a graphical-object bearingsurface as set forth in claim 4, comprising, for a logical block that isa partial matrix in the bit matrix V, in which any one matrix elementv(i,j) of the bit matrix V is the starting point, and the array lengthalong the i-axis is the offset a, with the positive direction of thei-axis being a main scanning direction and the positive direction of thej-axis being a sub-scanning direction of the digital informationcapturing means, unifying any of the constituent elements of saidlogical block so as to form a bit array that is identical with a partialarray of the reference-bit array B.
 6. A bit-data decoding method as setforth in claim 5, wherein the reference-bit array B is constituted sothat partial arrays of predetermined length obtained with arbitraryoffsets differ from each other.
 7. A bit-data decoding method as setforth in claim 5, further comprising replacing the matrix element v(i,j)constituting said logical block and forming the terminus of the array inthe main scanning direction, on the condition that either of the matrixelements v(i−a,j+1) and v(i+a,j−1) neighbors said logical block, witheither of said matrix elements, to thereby configure of a new logicalblock.
 8. A bit-data decoding method as set forth in claim 5, furthercomprising removing from said logical block the matrix elementconstituting the first in said bit array, and adding the matrix elementadjacent, in the main scanning direction, to the matrix elementconstituting the last in said bit array, to thereby configure a newlogical block.
 9. A bit-data decoding method as set forth in claim 5,further comprising removing from said logical block the matrix elementconstituting the last in said bit array, and adding the matrix elementadjacent, in the opposite direction from the main scanning direction, tothe matrix element constituting the first in said bit array, to therebyconfigure a new logical block.